Expose wrap functions on ConnInfo

- Remove rarely used ScanPlan.Scan arguments
- Plus other refactorings and fixes that fell out of this change.
- Plus rows Scan now handles checking for changed type.

pgtype/array_codec.go

@@ -204,7 +204,12 @@ func (c *ArrayCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target int
 		return nil
 	}
 
-	return (*scanPlanArrayCodec)(c)
+	return &scanPlanArrayCodec{
+		arrayCodec: c,
+		ci:         ci,
+		oid:        oid,
+		formatCode: format,
+	}
 }
 
 func (c *ArrayCodec) decodeBinary(ci *ConnInfo, arrayOID uint32, src []byte, array ArraySetter) error {
@@ -244,7 +249,7 @@ func (c *ArrayCodec) decodeBinary(ci *ConnInfo, arrayOID uint32, src []byte, arr
 			elemSrc = src[rp : rp+elemLen]
 			rp += elemLen
 		}
-		err = elementScanPlan.Scan(ci, c.ElementOID, BinaryFormatCode, elemSrc, elem)
+		err = elementScanPlan.Scan(elemSrc, elem)
 		if err != nil {
 			return err
 		}
@@ -286,7 +291,7 @@ func (c *ArrayCodec) decodeText(ci *ConnInfo, arrayOID uint32, src []byte, array
 			elemSrc = []byte(s)
 		}
 
-		err = elementScanPlan.Scan(ci, c.ElementOID, TextFormatCode, elemSrc, elem)
+		err = elementScanPlan.Scan(elemSrc, elem)
 		if err != nil {
 			return err
 		}
@@ -295,15 +300,23 @@ func (c *ArrayCodec) decodeText(ci *ConnInfo, arrayOID uint32, src []byte, array
 	return nil
 }
 
-type scanPlanArrayCodec ArrayCodec
+type scanPlanArrayCodec struct {
+	arrayCodec *ArrayCodec
+	ci         *ConnInfo
+	oid        uint32
+	formatCode int16
+}
 
-func (spac *scanPlanArrayCodec) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (spac *scanPlanArrayCodec) Scan(src []byte, dst interface{}) error {
-	c := (*ArrayCodec)(spac)
+	c := spac.arrayCodec
+	ci := spac.ci
+	oid := spac.oid
+	formatCode := spac.formatCode
 
 	array, err := makeArraySetter(dst)
 	if err != nil {
 		newPlan := ci.PlanScan(oid, formatCode, dst)
-		return newPlan.Scan(ci, oid, formatCode, src, dst)
+		return newPlan.Scan(src, dst)
 	}
 
 	if src == nil {

pgtype/bits.go

@@ -41,7 +41,7 @@ func (dst *Bits) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToBitsScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), dst)
+		return scanPlanTextAnyToBitsScanner{}.Scan([]byte(src), dst)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -163,7 +163,7 @@ func (c BitsCodec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byt
 
 type scanPlanBinaryBitsToBitsScanner struct{}
 
-func (scanPlanBinaryBitsToBitsScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryBitsToBitsScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(BitsScanner)
 
 	if src == nil {
@@ -182,7 +182,7 @@ func (scanPlanBinaryBitsToBitsScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToBitsScanner struct{}
 
-func (scanPlanTextAnyToBitsScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToBitsScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(BitsScanner)
 
 	if src == nil {

pgtype/bool.go

@@ -238,7 +238,7 @@ func (c BoolCodec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byt
 
 type scanPlanBinaryBoolToBool struct{}
 
-func (scanPlanBinaryBoolToBool) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryBoolToBool) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -259,7 +259,7 @@ func (scanPlanBinaryBoolToBool) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanTextAnyToBool struct{}
 
-func (scanPlanTextAnyToBool) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToBool) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -280,7 +280,7 @@ func (scanPlanTextAnyToBool) Scan(ci *ConnInfo, oid uint32, formatCode int16, sr
 
 type scanPlanBinaryBoolToBoolScanner struct{}
 
-func (scanPlanBinaryBoolToBoolScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryBoolToBoolScanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(BoolScanner)
 	if !ok {
 		return ErrScanTargetTypeChanged
@@ -299,7 +299,7 @@ func (scanPlanBinaryBoolToBoolScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToBoolScanner struct{}
 
-func (scanPlanTextAnyToBoolScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToBoolScanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(BoolScanner)
 	if !ok {
 		return ErrScanTargetTypeChanged

pgtype/box.go

@@ -42,7 +42,7 @@ func (dst *Box) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToBoxScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), dst)
+		return scanPlanTextAnyToBoxScanner{}.Scan([]byte(src), dst)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -146,7 +146,7 @@ func (BoxCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfac
 
 type scanPlanBinaryBoxToBoxScanner struct{}
 
-func (scanPlanBinaryBoxToBoxScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryBoxToBoxScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(BoxScanner)
 
 	if src == nil {
@@ -173,7 +173,7 @@ func (scanPlanBinaryBoxToBoxScanner) Scan(ci *ConnInfo, oid uint32, formatCode i
 
 type scanPlanTextAnyToBoxScanner struct{}
 
-func (scanPlanTextAnyToBoxScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToBoxScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(BoxScanner)
 
 	if src == nil {

pgtype/builtin_wrappers.go

@@ -494,6 +494,8 @@ func (w netIPNetWrapper) InetValue() (Inet, error) {
 
 type netIPWrapper net.IP
 
+func (w netIPWrapper) SkipUnderlyingTypePlan() {}
+
 func (w *netIPWrapper) ScanInet(v Inet) error {
 	if !v.Valid {
 		*w = nil
@@ -578,6 +580,26 @@ func (w byte16Wrapper) UUIDValue() (UUID, error) {
 
 type byteSliceWrapper []byte
 
+func (w byteSliceWrapper) SkipUnderlyingTypePlan() {}
+
+func (w *byteSliceWrapper) ScanText(v Text) error {
+	if !v.Valid {
+		*w = nil
+		return nil
+	}
+
+	*w = byteSliceWrapper(v.String)
+	return nil
+}
+
+func (w byteSliceWrapper) TextValue() (Text, error) {
+	if w == nil {
+		return Text{}, nil
+	}
+
+	return Text{String: string(w), Valid: true}, nil
+}
+
 func (w *byteSliceWrapper) ScanUUID(v UUID) error {
 	if !v.Valid {
 		*w = nil

pgtype/bytea.go

@@ -49,7 +49,7 @@ type UndecodedBytes []byte
 
 type scanPlanAnyToUndecodedBytes struct{}
 
-func (scanPlanAnyToUndecodedBytes) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanAnyToUndecodedBytes) Scan(src []byte, dst interface{}) error {
 	dstBuf := dst.(*UndecodedBytes)
 	if src == nil {
 		*dstBuf = nil
@@ -170,7 +170,7 @@ func (ByteaCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interf
 
 type scanPlanBinaryBytesToBytes struct{}
 
-func (scanPlanBinaryBytesToBytes) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryBytesToBytes) Scan(src []byte, dst interface{}) error {
 	dstBuf := dst.(*[]byte)
 	if src == nil {
 		*dstBuf = nil
@@ -184,14 +184,14 @@ func (scanPlanBinaryBytesToBytes) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryBytesToBytesScanner struct{}
 
-func (scanPlanBinaryBytesToBytesScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryBytesToBytesScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(BytesScanner)
 	return scanner.ScanBytes(src)
 }
 
 type scanPlanTextByteaToBytes struct{}
 
-func (scanPlanTextByteaToBytes) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextByteaToBytes) Scan(src []byte, dst interface{}) error {
 	dstBuf := dst.(*[]byte)
 	if src == nil {
 		*dstBuf = nil
@@ -209,7 +209,7 @@ func (scanPlanTextByteaToBytes) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanTextByteaToBytesScanner struct{}
 
-func (scanPlanTextByteaToBytesScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextByteaToBytesScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(BytesScanner)
 	buf, err := decodeHexBytea(src)
 	if err != nil {

pgtype/circle.go

@@ -43,7 +43,7 @@ func (dst *Circle) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToCircleScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), dst)
+		return scanPlanTextAnyToCircleScanner{}.Scan([]byte(src), dst)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -161,7 +161,7 @@ func (c CircleCodec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []b
 
 type scanPlanBinaryCircleToCircleScanner struct{}
 
-func (scanPlanBinaryCircleToCircleScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryCircleToCircleScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(CircleScanner)
 
 	if src == nil {
@@ -185,7 +185,7 @@ func (scanPlanBinaryCircleToCircleScanner) Scan(ci *ConnInfo, oid uint32, format
 
 type scanPlanTextAnyToCircleScanner struct{}
 
-func (scanPlanTextAnyToCircleScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToCircleScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(CircleScanner)
 
 	if src == nil {

pgtype/date.go

@@ -47,7 +47,7 @@ func (dst *Date) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToDateScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), dst)
+		return scanPlanTextAnyToDateScanner{}.Scan([]byte(src), dst)
 	case time.Time:
 		*dst = Date{Time: src, Valid: true}
 		return nil
@@ -216,7 +216,7 @@ func (DateCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfa
 
 type scanPlanBinaryDateToDateScanner struct{}
 
-func (scanPlanBinaryDateToDateScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryDateToDateScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(DateScanner)
 
 	if src == nil {
@@ -242,7 +242,7 @@ func (scanPlanBinaryDateToDateScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToDateScanner struct{}
 
-func (scanPlanTextAnyToDateScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToDateScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(DateScanner)
 
 	if src == nil {

pgtype/enum_codec.go

@@ -86,7 +86,7 @@ type scanPlanTextAnyToEnumString struct {
 	codec *EnumCodec
 }
 
-func (plan *scanPlanTextAnyToEnumString) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *scanPlanTextAnyToEnumString) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -101,7 +101,7 @@ type scanPlanTextAnyToEnumTextScanner struct {
 	codec *EnumCodec
 }
 
-func (plan *scanPlanTextAnyToEnumTextScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *scanPlanTextAnyToEnumTextScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TextScanner)
 
 	if src == nil {

pgtype/float4.go

@@ -164,7 +164,7 @@ func (Float4Codec) PlanScan(ci *ConnInfo, oid uint32, format int16, target inter
 
 type scanPlanBinaryFloat4ToFloat32 struct{}
 
-func (scanPlanBinaryFloat4ToFloat32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryFloat4ToFloat32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -182,7 +182,7 @@ func (scanPlanBinaryFloat4ToFloat32) Scan(ci *ConnInfo, oid uint32, formatCode i
 
 type scanPlanBinaryFloat4ToFloat64Scanner struct{}
 
-func (scanPlanBinaryFloat4ToFloat64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryFloat4ToFloat64Scanner) Scan(src []byte, dst interface{}) error {
 	s := (dst).(Float64Scanner)
 
 	if src == nil {
@@ -199,7 +199,7 @@ func (scanPlanBinaryFloat4ToFloat64Scanner) Scan(ci *ConnInfo, oid uint32, forma
 
 type scanPlanBinaryFloat4ToInt64Scanner struct{}
 
-func (scanPlanBinaryFloat4ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryFloat4ToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	s := (dst).(Int64Scanner)
 
 	if src == nil {
@@ -222,7 +222,7 @@ func (scanPlanBinaryFloat4ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatC
 
 type scanPlanTextAnyToFloat32 struct{}
 
-func (scanPlanTextAnyToFloat32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToFloat32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}

pgtype/float8.go

@@ -202,7 +202,7 @@ func (Float8Codec) PlanScan(ci *ConnInfo, oid uint32, format int16, target inter
 
 type scanPlanBinaryFloat8ToFloat64 struct{}
 
-func (scanPlanBinaryFloat8ToFloat64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryFloat8ToFloat64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -220,7 +220,7 @@ func (scanPlanBinaryFloat8ToFloat64) Scan(ci *ConnInfo, oid uint32, formatCode i
 
 type scanPlanBinaryFloat8ToFloat64Scanner struct{}
 
-func (scanPlanBinaryFloat8ToFloat64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryFloat8ToFloat64Scanner) Scan(src []byte, dst interface{}) error {
 	s := (dst).(Float64Scanner)
 
 	if src == nil {
@@ -237,7 +237,7 @@ func (scanPlanBinaryFloat8ToFloat64Scanner) Scan(ci *ConnInfo, oid uint32, forma
 
 type scanPlanBinaryFloat8ToInt64Scanner struct{}
 
-func (scanPlanBinaryFloat8ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryFloat8ToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	s := (dst).(Int64Scanner)
 
 	if src == nil {
@@ -260,7 +260,7 @@ func (scanPlanBinaryFloat8ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatC
 
 type scanPlanTextAnyToFloat64 struct{}
 
-func (scanPlanTextAnyToFloat64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToFloat64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -278,7 +278,7 @@ func (scanPlanTextAnyToFloat64) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanTextAnyToFloat64Scanner struct{}
 
-func (scanPlanTextAnyToFloat64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToFloat64Scanner) Scan(src []byte, dst interface{}) error {
 	s := (dst).(Float64Scanner)
 
 	if src == nil {

pgtype/hstore.go

@@ -43,7 +43,7 @@ func (h *Hstore) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToHstoreScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), h)
+		return scanPlanTextAnyToHstoreScanner{}.Scan([]byte(src), h)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -170,7 +170,7 @@ func (HstoreCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target inter
 
 type scanPlanBinaryHstoreToHstoreScanner struct{}
 
-func (scanPlanBinaryHstoreToHstoreScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryHstoreToHstoreScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(HstoreScanner)
 
 	if src == nil {
@@ -213,7 +213,7 @@ func (scanPlanBinaryHstoreToHstoreScanner) Scan(ci *ConnInfo, oid uint32, format
 		}
 
 		var value Text
-		err := scanPlanTextAnyToTextScanner{}.Scan(ci, TextOID, TextFormatCode, valueBuf, &value)
+		err := scanPlanTextAnyToTextScanner{}.Scan(valueBuf, &value)
 		if err != nil {
 			return err
 		}
@@ -230,7 +230,7 @@ func (scanPlanBinaryHstoreToHstoreScanner) Scan(ci *ConnInfo, oid uint32, format
 
 type scanPlanTextAnyToHstoreScanner struct{}
 
-func (scanPlanTextAnyToHstoreScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToHstoreScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(HstoreScanner)
 
 	if src == nil {

pgtype/inet.go

@@ -46,7 +46,7 @@ func (dst *Inet) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToInetScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), dst)
+		return scanPlanTextAnyToInetScanner{}.Scan([]byte(src), dst)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -182,7 +182,7 @@ func (c InetCodec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byt
 
 type scanPlanBinaryInetToInetScanner struct{}
 
-func (scanPlanBinaryInetToInetScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInetToInetScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(InetScanner)
 
 	if src == nil {
@@ -211,7 +211,7 @@ func (scanPlanBinaryInetToInetScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToInetScanner struct{}
 
-func (scanPlanTextAnyToInetScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInetScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(InetScanner)
 
 	if src == nil {

pgtype/int.go

@@ -292,7 +292,7 @@ func (c Int2Codec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byt
 
 type scanPlanBinaryInt2ToInt8 struct{}
 
-func (scanPlanBinaryInt2ToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToInt8) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -320,7 +320,7 @@ func (scanPlanBinaryInt2ToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt2ToUint8 struct{}
 
-func (scanPlanBinaryInt2ToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToUint8) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -350,7 +350,7 @@ func (scanPlanBinaryInt2ToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt2ToInt16 struct{}
 
-func (scanPlanBinaryInt2ToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToInt16) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -371,7 +371,7 @@ func (scanPlanBinaryInt2ToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt2ToUint16 struct{}
 
-func (scanPlanBinaryInt2ToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToUint16) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -397,7 +397,7 @@ func (scanPlanBinaryInt2ToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt2ToInt32 struct{}
 
-func (scanPlanBinaryInt2ToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToInt32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -418,7 +418,7 @@ func (scanPlanBinaryInt2ToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt2ToUint32 struct{}
 
-func (scanPlanBinaryInt2ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToUint32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -444,7 +444,7 @@ func (scanPlanBinaryInt2ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt2ToInt64 struct{}
 
-func (scanPlanBinaryInt2ToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToInt64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -465,7 +465,7 @@ func (scanPlanBinaryInt2ToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt2ToUint64 struct{}
 
-func (scanPlanBinaryInt2ToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToUint64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -491,7 +491,7 @@ func (scanPlanBinaryInt2ToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt2ToInt struct{}
 
-func (scanPlanBinaryInt2ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToInt) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -512,7 +512,7 @@ func (scanPlanBinaryInt2ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt2ToUint struct{}
 
-func (scanPlanBinaryInt2ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToUint) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -538,7 +538,7 @@ func (scanPlanBinaryInt2ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt2ToInt64Scanner struct{}
 
-func (scanPlanBinaryInt2ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt2ToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(Int64Scanner)
 	if !ok {
 		return ErrScanTargetTypeChanged
@@ -829,7 +829,7 @@ func (c Int4Codec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byt
 
 type scanPlanBinaryInt4ToInt8 struct{}
 
-func (scanPlanBinaryInt4ToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToInt8) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -857,7 +857,7 @@ func (scanPlanBinaryInt4ToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt4ToUint8 struct{}
 
-func (scanPlanBinaryInt4ToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToUint8) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -887,7 +887,7 @@ func (scanPlanBinaryInt4ToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt4ToInt16 struct{}
 
-func (scanPlanBinaryInt4ToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToInt16) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -915,7 +915,7 @@ func (scanPlanBinaryInt4ToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt4ToUint16 struct{}
 
-func (scanPlanBinaryInt4ToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToUint16) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -945,7 +945,7 @@ func (scanPlanBinaryInt4ToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt4ToInt32 struct{}
 
-func (scanPlanBinaryInt4ToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToInt32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -966,7 +966,7 @@ func (scanPlanBinaryInt4ToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt4ToUint32 struct{}
 
-func (scanPlanBinaryInt4ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToUint32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -992,7 +992,7 @@ func (scanPlanBinaryInt4ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt4ToInt64 struct{}
 
-func (scanPlanBinaryInt4ToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToInt64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1013,7 +1013,7 @@ func (scanPlanBinaryInt4ToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt4ToUint64 struct{}
 
-func (scanPlanBinaryInt4ToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToUint64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1039,7 +1039,7 @@ func (scanPlanBinaryInt4ToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt4ToInt struct{}
 
-func (scanPlanBinaryInt4ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToInt) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1060,7 +1060,7 @@ func (scanPlanBinaryInt4ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt4ToUint struct{}
 
-func (scanPlanBinaryInt4ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToUint) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1086,7 +1086,7 @@ func (scanPlanBinaryInt4ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt4ToInt64Scanner struct{}
 
-func (scanPlanBinaryInt4ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt4ToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(Int64Scanner)
 	if !ok {
 		return ErrScanTargetTypeChanged
@@ -1377,7 +1377,7 @@ func (c Int8Codec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byt
 
 type scanPlanBinaryInt8ToInt8 struct{}
 
-func (scanPlanBinaryInt8ToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToInt8) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1405,7 +1405,7 @@ func (scanPlanBinaryInt8ToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt8ToUint8 struct{}
 
-func (scanPlanBinaryInt8ToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToUint8) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1435,7 +1435,7 @@ func (scanPlanBinaryInt8ToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt8ToInt16 struct{}
 
-func (scanPlanBinaryInt8ToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToInt16) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1463,7 +1463,7 @@ func (scanPlanBinaryInt8ToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt8ToUint16 struct{}
 
-func (scanPlanBinaryInt8ToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToUint16) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1493,7 +1493,7 @@ func (scanPlanBinaryInt8ToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt8ToInt32 struct{}
 
-func (scanPlanBinaryInt8ToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToInt32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1521,7 +1521,7 @@ func (scanPlanBinaryInt8ToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt8ToUint32 struct{}
 
-func (scanPlanBinaryInt8ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToUint32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1551,7 +1551,7 @@ func (scanPlanBinaryInt8ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt8ToInt64 struct{}
 
-func (scanPlanBinaryInt8ToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToInt64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1572,7 +1572,7 @@ func (scanPlanBinaryInt8ToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanBinaryInt8ToUint64 struct{}
 
-func (scanPlanBinaryInt8ToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToUint64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1598,7 +1598,7 @@ func (scanPlanBinaryInt8ToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int1
 
 type scanPlanBinaryInt8ToInt struct{}
 
-func (scanPlanBinaryInt8ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToInt) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1626,7 +1626,7 @@ func (scanPlanBinaryInt8ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt8ToUint struct{}
 
-func (scanPlanBinaryInt8ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToUint) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1656,7 +1656,7 @@ func (scanPlanBinaryInt8ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanBinaryInt8ToInt64Scanner struct{}
 
-func (scanPlanBinaryInt8ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt8ToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(Int64Scanner)
 	if !ok {
 		return ErrScanTargetTypeChanged
@@ -1677,7 +1677,7 @@ func (scanPlanBinaryInt8ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCod
 
 type scanPlanTextAnyToInt8 struct{}
 
-func (scanPlanTextAnyToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInt8) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1698,7 +1698,7 @@ func (scanPlanTextAnyToInt8) Scan(ci *ConnInfo, oid uint32, formatCode int16, sr
 
 type scanPlanTextAnyToUint8 struct{}
 
-func (scanPlanTextAnyToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToUint8) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1719,7 +1719,7 @@ func (scanPlanTextAnyToUint8) Scan(ci *ConnInfo, oid uint32, formatCode int16, s
 
 type scanPlanTextAnyToInt16 struct{}
 
-func (scanPlanTextAnyToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInt16) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1740,7 +1740,7 @@ func (scanPlanTextAnyToInt16) Scan(ci *ConnInfo, oid uint32, formatCode int16, s
 
 type scanPlanTextAnyToUint16 struct{}
 
-func (scanPlanTextAnyToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToUint16) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1761,7 +1761,7 @@ func (scanPlanTextAnyToUint16) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanTextAnyToInt32 struct{}
 
-func (scanPlanTextAnyToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInt32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1782,7 +1782,7 @@ func (scanPlanTextAnyToInt32) Scan(ci *ConnInfo, oid uint32, formatCode int16, s
 
 type scanPlanTextAnyToUint32 struct{}
 
-func (scanPlanTextAnyToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToUint32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1803,7 +1803,7 @@ func (scanPlanTextAnyToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanTextAnyToInt64 struct{}
 
-func (scanPlanTextAnyToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInt64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1824,7 +1824,7 @@ func (scanPlanTextAnyToInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16, s
 
 type scanPlanTextAnyToUint64 struct{}
 
-func (scanPlanTextAnyToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToUint64) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1845,7 +1845,7 @@ func (scanPlanTextAnyToUint64) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanTextAnyToInt struct{}
 
-func (scanPlanTextAnyToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInt) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1866,7 +1866,7 @@ func (scanPlanTextAnyToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16, src
 
 type scanPlanTextAnyToUint struct{}
 
-func (scanPlanTextAnyToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToUint) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -1887,7 +1887,7 @@ func (scanPlanTextAnyToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, sr
 
 type scanPlanTextAnyToInt64Scanner struct{}
 
-func (scanPlanTextAnyToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(Int64Scanner)
 	if !ok {
 		return ErrScanTargetTypeChanged

pgtype/int.go.erb

@@ -295,7 +295,7 @@ func (c Int<%= pg_byte_size %>Codec) DecodeValue(ci *ConnInfo, oid uint32, forma
 <% [8, 16, 32, 64].each do |dst_bit_size| %>
 type scanPlanBinaryInt<%= pg_byte_size %>ToInt<%= dst_bit_size %> struct{}
 
-func (scanPlanBinaryInt<%= pg_byte_size %>ToInt<%= dst_bit_size %>) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt<%= pg_byte_size %>ToInt<%= dst_bit_size %>) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -329,7 +329,7 @@ func (scanPlanBinaryInt<%= pg_byte_size %>ToInt<%= dst_bit_size %>) Scan(ci *Con
 
 type scanPlanBinaryInt<%= pg_byte_size %>ToUint<%= dst_bit_size %> struct{}
 
-func (scanPlanBinaryInt<%= pg_byte_size %>ToUint<%= dst_bit_size %>) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt<%= pg_byte_size %>ToUint<%= dst_bit_size %>) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -361,7 +361,7 @@ func (scanPlanBinaryInt<%= pg_byte_size %>ToUint<%= dst_bit_size %>) Scan(ci *Co
 <%# PostgreSQL binary format integer to Go machine integers %>
 type scanPlanBinaryInt<%= pg_byte_size %>ToInt struct{}
 
-func (scanPlanBinaryInt<%= pg_byte_size %>ToInt) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt<%= pg_byte_size %>ToInt) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -393,7 +393,7 @@ func (scanPlanBinaryInt<%= pg_byte_size %>ToInt) Scan(ci *ConnInfo, oid uint32,
 
 type scanPlanBinaryInt<%= pg_byte_size %>ToUint struct{}
 
-func (scanPlanBinaryInt<%= pg_byte_size %>ToUint) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt<%= pg_byte_size %>ToUint) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -424,7 +424,7 @@ func (scanPlanBinaryInt<%= pg_byte_size %>ToUint) Scan(ci *ConnInfo, oid uint32,
 <%# PostgreSQL binary format integer to Go Int64Scanner %>
 type scanPlanBinaryInt<%= pg_byte_size %>ToInt64Scanner struct{}
 
-func (scanPlanBinaryInt<%= pg_byte_size %>ToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryInt<%= pg_byte_size %>ToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(Int64Scanner)
 	if !ok {
 		return ErrScanTargetTypeChanged
@@ -455,7 +455,7 @@ func (scanPlanBinaryInt<%= pg_byte_size %>ToInt64Scanner) Scan(ci *ConnInfo, oid
 ].each do |type_suffix, bit_size| %>
 type scanPlanTextAnyToInt<%= type_suffix %> struct{}
 
-func (scanPlanTextAnyToInt<%= type_suffix %>) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInt<%= type_suffix %>) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -476,7 +476,7 @@ func (scanPlanTextAnyToInt<%= type_suffix %>) Scan(ci *ConnInfo, oid uint32, for
 
 type scanPlanTextAnyToUint<%= type_suffix %> struct{}
 
-func (scanPlanTextAnyToUint<%= type_suffix %>) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToUint<%= type_suffix %>) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -498,7 +498,7 @@ func (scanPlanTextAnyToUint<%= type_suffix %>) Scan(ci *ConnInfo, oid uint32, fo
 
 type scanPlanTextAnyToInt64Scanner struct{}
 
-func (scanPlanTextAnyToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(Int64Scanner)
 	if !ok {
 		return ErrScanTargetTypeChanged

pgtype/interval.go

@@ -51,7 +51,7 @@ func (interval *Interval) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToIntervalScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), interval)
+		return scanPlanTextAnyToIntervalScanner{}.Scan([]byte(src), interval)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -171,7 +171,7 @@ func (IntervalCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target int
 
 type scanPlanBinaryIntervalToIntervalScanner struct{}
 
-func (scanPlanBinaryIntervalToIntervalScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryIntervalToIntervalScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(IntervalScanner)
 
 	if src == nil {
@@ -191,7 +191,7 @@ func (scanPlanBinaryIntervalToIntervalScanner) Scan(ci *ConnInfo, oid uint32, fo
 
 type scanPlanTextAnyToIntervalScanner struct{}
 
-func (scanPlanTextAnyToIntervalScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToIntervalScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(IntervalScanner)
 
 	if src == nil {

pgtype/json.go

@@ -65,7 +65,7 @@ func (JSONCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfa
 
 type scanPlanAnyToString struct{}
 
-func (scanPlanAnyToString) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanAnyToString) Scan(src []byte, dst interface{}) error {
 	p := dst.(*string)
 	*p = string(src)
 	return nil
@@ -73,7 +73,7 @@ func (scanPlanAnyToString) Scan(ci *ConnInfo, oid uint32, formatCode int16, src
 
 type scanPlanJSONToByteSlice struct{}
 
-func (scanPlanJSONToByteSlice) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanJSONToByteSlice) Scan(src []byte, dst interface{}) error {
 	dstBuf := dst.(*[]byte)
 	if src == nil {
 		*dstBuf = nil
@@ -87,14 +87,14 @@ func (scanPlanJSONToByteSlice) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanJSONToBytesScanner struct{}
 
-func (scanPlanJSONToBytesScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanJSONToBytesScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(BytesScanner)
 	return scanner.ScanBytes(src)
 }
 
 type scanPlanJSONToJSONUnmarshal struct{}
 
-func (scanPlanJSONToJSONUnmarshal) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanJSONToJSONUnmarshal) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		dstValue := reflect.ValueOf(dst)
 		if dstValue.Kind() == reflect.Ptr {

pgtype/jsonb.go

@@ -57,9 +57,9 @@ type scanPlanJSONBCodecBinaryUnwrapper struct {
 	textPlan ScanPlan
 }
 
-func (plan *scanPlanJSONBCodecBinaryUnwrapper) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *scanPlanJSONBCodecBinaryUnwrapper) Scan(src []byte, dst interface{}) error {
 	if src == nil {
-		return plan.textPlan.Scan(ci, oid, formatCode, src, dst)
+		return plan.textPlan.Scan(src, dst)
 	}
 
 	if len(src) == 0 {
@@ -70,7 +70,7 @@ func (plan *scanPlanJSONBCodecBinaryUnwrapper) Scan(ci *ConnInfo, oid uint32, fo
 		return fmt.Errorf("unknown jsonb version number %d", src[0])
 	}
 
-	return plan.textPlan.Scan(ci, oid, formatCode, src[1:], dst)
+	return plan.textPlan.Scan(src[1:], dst)
 }
 
 func (c JSONBCodec) DecodeDatabaseSQLValue(ci *ConnInfo, oid uint32, format int16, src []byte) (driver.Value, error) {

pgtype/line.go

@@ -46,7 +46,7 @@ func (line *Line) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToLineScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), line)
+		return scanPlanTextAnyToLineScanner{}.Scan([]byte(src), line)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -148,7 +148,7 @@ func (LineCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfa
 
 type scanPlanBinaryLineToLineScanner struct{}
 
-func (scanPlanBinaryLineToLineScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryLineToLineScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(LineScanner)
 
 	if src == nil {
@@ -173,7 +173,7 @@ func (scanPlanBinaryLineToLineScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToLineScanner struct{}
 
-func (scanPlanTextAnyToLineScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToLineScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(LineScanner)
 
 	if src == nil {

pgtype/lseg.go

@@ -42,7 +42,7 @@ func (lseg *Lseg) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToLsegScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), lseg)
+		return scanPlanTextAnyToLsegScanner{}.Scan([]byte(src), lseg)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -146,7 +146,7 @@ func (LsegCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfa
 
 type scanPlanBinaryLsegToLsegScanner struct{}
 
-func (scanPlanBinaryLsegToLsegScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryLsegToLsegScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(LsegScanner)
 
 	if src == nil {
@@ -173,7 +173,7 @@ func (scanPlanBinaryLsegToLsegScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToLsegScanner struct{}
 
-func (scanPlanTextAnyToLsegScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToLsegScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(LsegScanner)
 
 	if src == nil {

pgtype/macaddr.go

@@ -101,7 +101,7 @@ func (MacaddrCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target inte
 
 type scanPlanBinaryMacaddrToHardwareAddr struct{}
 
-func (scanPlanBinaryMacaddrToHardwareAddr) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryMacaddrToHardwareAddr) Scan(src []byte, dst interface{}) error {
 	dstBuf := dst.(*net.HardwareAddr)
 	if src == nil {
 		*dstBuf = nil
@@ -115,7 +115,7 @@ func (scanPlanBinaryMacaddrToHardwareAddr) Scan(ci *ConnInfo, oid uint32, format
 
 type scanPlanBinaryMacaddrToTextScanner struct{}
 
-func (scanPlanBinaryMacaddrToTextScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryMacaddrToTextScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TextScanner)
 	if src == nil {
 		return scanner.ScanText(Text{})
@@ -126,7 +126,7 @@ func (scanPlanBinaryMacaddrToTextScanner) Scan(ci *ConnInfo, oid uint32, formatC
 
 type scanPlanTextMacaddrToHardwareAddr struct{}
 
-func (scanPlanTextMacaddrToHardwareAddr) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextMacaddrToHardwareAddr) Scan(src []byte, dst interface{}) error {
 	p := dst.(*net.HardwareAddr)
 
 	if src == nil {

pgtype/numeric.go

@@ -175,7 +175,7 @@ func (n *Numeric) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToNumericScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), n)
+		return scanPlanTextAnyToNumericScanner{}.Scan([]byte(src), n)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -522,7 +522,7 @@ func (NumericCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target inte
 
 type scanPlanBinaryNumericToNumericScanner struct{}
 
-func (scanPlanBinaryNumericToNumericScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryNumericToNumericScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(NumericScanner)
 
 	if src == nil {
@@ -628,7 +628,7 @@ func (scanPlanBinaryNumericToNumericScanner) Scan(ci *ConnInfo, oid uint32, form
 
 type scanPlanBinaryNumericToFloat64Scanner struct{}
 
-func (scanPlanBinaryNumericToFloat64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryNumericToFloat64Scanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(Float64Scanner)
 
 	if src == nil {
@@ -637,7 +637,7 @@ func (scanPlanBinaryNumericToFloat64Scanner) Scan(ci *ConnInfo, oid uint32, form
 
 	var n Numeric
 
-	err := scanPlanBinaryNumericToNumericScanner{}.Scan(ci, oid, formatCode, src, &n)
+	err := scanPlanBinaryNumericToNumericScanner{}.Scan(src, &n)
 	if err != nil {
 		return err
 	}
@@ -652,7 +652,7 @@ func (scanPlanBinaryNumericToFloat64Scanner) Scan(ci *ConnInfo, oid uint32, form
 
 type scanPlanBinaryNumericToInt64Scanner struct{}
 
-func (scanPlanBinaryNumericToInt64Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryNumericToInt64Scanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(Int64Scanner)
 
 	if src == nil {
@@ -661,7 +661,7 @@ func (scanPlanBinaryNumericToInt64Scanner) Scan(ci *ConnInfo, oid uint32, format
 
 	var n Numeric
 
-	err := scanPlanBinaryNumericToNumericScanner{}.Scan(ci, oid, formatCode, src, &n)
+	err := scanPlanBinaryNumericToNumericScanner{}.Scan(src, &n)
 	if err != nil {
 		return err
 	}
@@ -680,7 +680,7 @@ func (scanPlanBinaryNumericToInt64Scanner) Scan(ci *ConnInfo, oid uint32, format
 
 type scanPlanTextAnyToNumericScanner struct{}
 
-func (scanPlanTextAnyToNumericScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToNumericScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(NumericScanner)
 
 	if src == nil {

pgtype/numeric_test.go

@@ -64,7 +64,7 @@ func mustParseNumeric(t *testing.T, src string) pgtype.Numeric {
 	var n pgtype.Numeric
 	plan := pgtype.NumericCodec{}.PlanScan(nil, pgtype.NumericOID, pgtype.TextFormatCode, &n, false)
 	require.NotNil(t, plan)
-	err := plan.Scan(nil, pgtype.NumericOID, pgtype.TextFormatCode, []byte(src), &n)
+	err := plan.Scan([]byte(src), &n)
 	require.NoError(t, err)
 	return n
 }

pgtype/path.go

@@ -43,7 +43,7 @@ func (path *Path) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToPathScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), path)
+		return scanPlanTextAnyToPathScanner{}.Scan([]byte(src), path)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -173,7 +173,7 @@ func (PathCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfa
 
 type scanPlanBinaryPathToPathScanner struct{}
 
-func (scanPlanBinaryPathToPathScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryPathToPathScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(PathScanner)
 
 	if src == nil {
@@ -211,7 +211,7 @@ func (scanPlanBinaryPathToPathScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToPathScanner struct{}
 
-func (scanPlanTextAnyToPathScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToPathScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(PathScanner)
 
 	if src == nil {

pgtype/pgtype.go

@@ -3,10 +3,8 @@ package pgtype
 import (
 	"database/sql"
 	"database/sql/driver"
-	"encoding/binary"
 	"errors"
 	"fmt"
-	"math"
 	"net"
 	"reflect"
 	"time"
@@ -198,14 +196,14 @@ func NewConnInfo() *ConnInfo {
 
 		TryWrapEncodePlanFuncs: []TryWrapEncodePlanFunc{
 			TryWrapDerefPointerEncodePlan,
-			TryWrapFindUnderlyingTypeEncodePlan,
 			TryWrapBuiltinTypeEncodePlan,
+			TryWrapFindUnderlyingTypeEncodePlan,
 		},
 
 		TryWrapScanPlanFuncs: []TryWrapScanPlanFunc{
 			TryPointerPointerScanPlan,
-			TryFindUnderlyingTypeScanPlan,
 			TryWrapBuiltinTypeScanPlan,
+			TryFindUnderlyingTypeScanPlan,
 		},
 	}
 
@@ -409,22 +407,19 @@ type EncodePlan interface {
 
 // ScanPlan is a precompiled plan to scan into a type of destination.
 type ScanPlan interface {
-	// Scan scans src into dst. If the dst type has changed in an incompatible way a ScanPlan should automatically
+	// Scan scans src into target.
-	// replan and scan.
+	Scan(src []byte, target interface{}) error
-	Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error
 }
 
-type scanPlanDstResultDecoder struct{}
+type scanPlanCodecSQLScanner struct {
-
+	c          Codec
-func (scanPlanDstResultDecoder) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+	ci         *ConnInfo
-	newPlan := ci.PlanScan(oid, formatCode, dst)
+	oid        uint32
-	return newPlan.Scan(ci, oid, formatCode, src, dst)
+	formatCode int16
 }
 
-type scanPlanCodecSQLScanner struct{ c Codec }
+func (plan *scanPlanCodecSQLScanner) Scan(src []byte, dst interface{}) error {
-
+	value, err := plan.c.DecodeDatabaseSQLValue(plan.ci, plan.oid, plan.formatCode, src)
-func (plan *scanPlanCodecSQLScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
-	value, err := plan.c.DecodeDatabaseSQLValue(ci, oid, formatCode, src)
 	if err != nil {
 		return err
 	}
@@ -433,135 +428,56 @@ func (plan *scanPlanCodecSQLScanner) Scan(ci *ConnInfo, oid uint32, formatCode i
 	return scanner.Scan(value)
 }
 
-type scanPlanSQLScanner struct{}
+type scanPlanSQLScanner struct {
+	formatCode int16
+}
 
-func (scanPlanSQLScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *scanPlanSQLScanner) Scan(src []byte, dst interface{}) error {
 	scanner := dst.(sql.Scanner)
 	if src == nil {
 		// This is necessary because interface value []byte:nil does not equal nil:nil for the binary format path and the
 		// text format path would be converted to empty string.
 		return scanner.Scan(nil)
-	} else if formatCode == BinaryFormatCode {
+	} else if plan.formatCode == BinaryFormatCode {
 		return scanner.Scan(src)
 	} else {
 		return scanner.Scan(string(src))
 	}
 }
 
-type scanPlanReflection struct{}
-
-func (scanPlanReflection) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
-	// We might be given a pointer to something that implements the decoder interface(s),
-	// even though the pointer itself doesn't.
-	refVal := reflect.ValueOf(dst)
-	if refVal.Kind() == reflect.Ptr && refVal.Type().Elem().Kind() == reflect.Ptr {
-		// If the database returned NULL, then we set dest as nil to indicate that.
-		if src == nil {
-			nilPtr := reflect.Zero(refVal.Type().Elem())
-			refVal.Elem().Set(nilPtr)
-			return nil
-		}
-
-		// We need to allocate an element, and set the destination to it
-		// Then we can retry as that element.
-		elemPtr := reflect.New(refVal.Type().Elem().Elem())
-		refVal.Elem().Set(elemPtr)
-
-		plan := ci.PlanScan(oid, formatCode, elemPtr.Interface())
-		return plan.Scan(ci, oid, formatCode, src, elemPtr.Interface())
-	}
-
-	return scanUnknownType(oid, formatCode, src, dst)
-}
-
-type scanPlanBinaryInt64 struct{}
-
-func (scanPlanBinaryInt64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
-	if src == nil {
-		return fmt.Errorf("cannot scan null into %T", dst)
-	}
-
-	if len(src) != 8 {
-		return fmt.Errorf("invalid length for int8: %v", len(src))
-	}
-
-	if p, ok := (dst).(*int64); ok {
-		*p = int64(binary.BigEndian.Uint64(src))
-		return nil
-	}
-
-	newPlan := ci.PlanScan(oid, formatCode, dst)
-	return newPlan.Scan(ci, oid, formatCode, src, dst)
-}
-
-type scanPlanBinaryFloat32 struct{}
-
-func (scanPlanBinaryFloat32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
-	if src == nil {
-		return fmt.Errorf("cannot scan null into %T", dst)
-	}
-
-	if len(src) != 4 {
-		return fmt.Errorf("invalid length for int4: %v", len(src))
-	}
-
-	if p, ok := (dst).(*float32); ok {
-		n := int32(binary.BigEndian.Uint32(src))
-		*p = float32(math.Float32frombits(uint32(n)))
-		return nil
-	}
-
-	newPlan := ci.PlanScan(oid, formatCode, dst)
-	return newPlan.Scan(ci, oid, formatCode, src, dst)
-}
-
-type scanPlanBinaryFloat64 struct{}
-
-func (scanPlanBinaryFloat64) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
-	if src == nil {
-		return fmt.Errorf("cannot scan null into %T", dst)
-	}
-
-	if len(src) != 8 {
-		return fmt.Errorf("invalid length for int8: %v", len(src))
-	}
-
-	if p, ok := (dst).(*float64); ok {
-		n := int64(binary.BigEndian.Uint64(src))
-		*p = float64(math.Float64frombits(uint64(n)))
-		return nil
-	}
-
-	newPlan := ci.PlanScan(oid, formatCode, dst)
-	return newPlan.Scan(ci, oid, formatCode, src, dst)
-}
-
-type scanPlanBinaryBytes struct{}
-
-func (scanPlanBinaryBytes) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
-	if p, ok := (dst).(*[]byte); ok {
-		*p = src
-		return nil
-	}
-
-	newPlan := ci.PlanScan(oid, formatCode, dst)
-	return newPlan.Scan(ci, oid, formatCode, src, dst)
-}
-
 type scanPlanString struct{}
 
-func (scanPlanString) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanString) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
 
-	if p, ok := (dst).(*string); ok {
+	p := (dst).(*string)
-		*p = string(src)
+	*p = string(src)
+	return nil
+}
+
+type scanPlanAnyTextToBytes struct{}
+
+func (scanPlanAnyTextToBytes) Scan(src []byte, dst interface{}) error {
+	dstBuf := dst.(*[]byte)
+	if src == nil {
+		*dstBuf = nil
 		return nil
 	}
 
-	newPlan := ci.PlanScan(oid, formatCode, dst)
+	*dstBuf = make([]byte, len(src))
-	return newPlan.Scan(ci, oid, formatCode, src, dst)
+	copy(*dstBuf, src)
+	return nil
+}
+
+type scanPlanFail struct {
+	oid        uint32
+	formatCode int16
+}
+
+func (plan *scanPlanFail) Scan(src []byte, dst interface{}) error {
+	return fmt.Errorf("cannot scan OID %v in format %v into %T", plan.oid, plan.formatCode, dst)
 }
 
 // TryWrapScanPlanFunc is a function that tries to create a wrapper plan for target. If successful it returns a plan
@@ -577,12 +493,7 @@ type pointerPointerScanPlan struct {
 
 func (plan *pointerPointerScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *pointerPointerScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *pointerPointerScanPlan) Scan(src []byte, dst interface{}) error {
-	if plan.dstType != reflect.TypeOf(dst) {
-		newPlan := ci.PlanScan(oid, formatCode, dst)
-		return newPlan.Scan(ci, oid, formatCode, src, dst)
-	}
-
 	el := reflect.ValueOf(dst).Elem()
 	if src == nil {
 		el.Set(reflect.Zero(el.Type()))
@@ -590,7 +501,7 @@ func (plan *pointerPointerScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode in
 	}
 
 	el.Set(reflect.New(el.Type().Elem()))
-	return plan.next.Scan(ci, oid, formatCode, src, el.Interface())
+	return plan.next.Scan(src, el.Interface())
 }
 
 // TryPointerPointerScanPlan handles a pointer to a pointer by setting the target to nil for SQL NULL and allocating and
@@ -636,13 +547,8 @@ type underlyingTypeScanPlan struct {
 
 func (plan *underlyingTypeScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *underlyingTypeScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *underlyingTypeScanPlan) Scan(src []byte, dst interface{}) error {
-	if plan.dstType != reflect.TypeOf(dst) {
+	return plan.next.Scan(src, reflect.ValueOf(dst).Convert(plan.nextDstType).Interface())
-		newPlan := ci.PlanScan(oid, formatCode, dst)
-		return newPlan.Scan(ci, oid, formatCode, src, dst)
-	}
-
-	return plan.next.Scan(ci, oid, formatCode, src, reflect.ValueOf(dst).Convert(plan.nextDstType).Interface())
 }
 
 // TryFindUnderlyingTypeScanPlan tries to convert to a Go builtin type. e.g. If value was of type MyString and
@@ -657,9 +563,17 @@ func TryFindUnderlyingTypeScanPlan(dst interface{}) (plan WrappedScanPlanNextSet
 	if dstValue.Kind() == reflect.Ptr {
 		elemValue := dstValue.Elem()
 		nextDstType := elemKindToPointerTypes[elemValue.Kind()]
+		if nextDstType == nil && elemValue.Kind() == reflect.Slice {
+			if elemValue.Type().Elem().Kind() == reflect.Uint8 {
+				var v *[]byte
+				nextDstType = reflect.TypeOf(v)
+			}
+		}
+
 		if nextDstType != nil && dstValue.Type() != nextDstType {
 			return &underlyingTypeScanPlan{dstType: dstValue.Type(), nextDstType: nextDstType}, dstValue.Convert(nextDstType).Interface(), true
 		}
+
 	}
 
 	return nil, nil, false
@@ -728,8 +642,8 @@ type wrapInt8ScanPlan struct {
 
 func (plan *wrapInt8ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapInt8ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapInt8ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*int8Wrapper)(dst.(*int8)))
+	return plan.next.Scan(src, (*int8Wrapper)(dst.(*int8)))
 }
 
 type wrapInt16ScanPlan struct {
@@ -738,8 +652,8 @@ type wrapInt16ScanPlan struct {
 
 func (plan *wrapInt16ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapInt16ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapInt16ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*int16Wrapper)(dst.(*int16)))
+	return plan.next.Scan(src, (*int16Wrapper)(dst.(*int16)))
 }
 
 type wrapInt32ScanPlan struct {
@@ -748,8 +662,8 @@ type wrapInt32ScanPlan struct {
 
 func (plan *wrapInt32ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapInt32ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapInt32ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*int32Wrapper)(dst.(*int32)))
+	return plan.next.Scan(src, (*int32Wrapper)(dst.(*int32)))
 }
 
 type wrapInt64ScanPlan struct {
@@ -758,8 +672,8 @@ type wrapInt64ScanPlan struct {
 
 func (plan *wrapInt64ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapInt64ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapInt64ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*int64Wrapper)(dst.(*int64)))
+	return plan.next.Scan(src, (*int64Wrapper)(dst.(*int64)))
 }
 
 type wrapIntScanPlan struct {
@@ -768,8 +682,8 @@ type wrapIntScanPlan struct {
 
 func (plan *wrapIntScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapIntScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapIntScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*intWrapper)(dst.(*int)))
+	return plan.next.Scan(src, (*intWrapper)(dst.(*int)))
 }
 
 type wrapUint8ScanPlan struct {
@@ -778,8 +692,8 @@ type wrapUint8ScanPlan struct {
 
 func (plan *wrapUint8ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapUint8ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapUint8ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*uint8Wrapper)(dst.(*uint8)))
+	return plan.next.Scan(src, (*uint8Wrapper)(dst.(*uint8)))
 }
 
 type wrapUint16ScanPlan struct {
@@ -788,8 +702,8 @@ type wrapUint16ScanPlan struct {
 
 func (plan *wrapUint16ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapUint16ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapUint16ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*uint16Wrapper)(dst.(*uint16)))
+	return plan.next.Scan(src, (*uint16Wrapper)(dst.(*uint16)))
 }
 
 type wrapUint32ScanPlan struct {
@@ -798,8 +712,8 @@ type wrapUint32ScanPlan struct {
 
 func (plan *wrapUint32ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapUint32ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapUint32ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*uint32Wrapper)(dst.(*uint32)))
+	return plan.next.Scan(src, (*uint32Wrapper)(dst.(*uint32)))
 }
 
 type wrapUint64ScanPlan struct {
@@ -808,8 +722,8 @@ type wrapUint64ScanPlan struct {
 
 func (plan *wrapUint64ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapUint64ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapUint64ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*uint64Wrapper)(dst.(*uint64)))
+	return plan.next.Scan(src, (*uint64Wrapper)(dst.(*uint64)))
 }
 
 type wrapUintScanPlan struct {
@@ -818,8 +732,8 @@ type wrapUintScanPlan struct {
 
 func (plan *wrapUintScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapUintScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapUintScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*uintWrapper)(dst.(*uint)))
+	return plan.next.Scan(src, (*uintWrapper)(dst.(*uint)))
 }
 
 type wrapFloat32ScanPlan struct {
@@ -828,8 +742,8 @@ type wrapFloat32ScanPlan struct {
 
 func (plan *wrapFloat32ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapFloat32ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapFloat32ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*float32Wrapper)(dst.(*float32)))
+	return plan.next.Scan(src, (*float32Wrapper)(dst.(*float32)))
 }
 
 type wrapFloat64ScanPlan struct {
@@ -838,8 +752,8 @@ type wrapFloat64ScanPlan struct {
 
 func (plan *wrapFloat64ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapFloat64ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapFloat64ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*float64Wrapper)(dst.(*float64)))
+	return plan.next.Scan(src, (*float64Wrapper)(dst.(*float64)))
 }
 
 type wrapStringScanPlan struct {
@@ -848,8 +762,8 @@ type wrapStringScanPlan struct {
 
 func (plan *wrapStringScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapStringScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapStringScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*stringWrapper)(dst.(*string)))
+	return plan.next.Scan(src, (*stringWrapper)(dst.(*string)))
 }
 
 type wrapTimeScanPlan struct {
@@ -858,8 +772,8 @@ type wrapTimeScanPlan struct {
 
 func (plan *wrapTimeScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapTimeScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapTimeScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*timeWrapper)(dst.(*time.Time)))
+	return plan.next.Scan(src, (*timeWrapper)(dst.(*time.Time)))
 }
 
 type wrapDurationScanPlan struct {
@@ -868,8 +782,8 @@ type wrapDurationScanPlan struct {
 
 func (plan *wrapDurationScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapDurationScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapDurationScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*durationWrapper)(dst.(*time.Duration)))
+	return plan.next.Scan(src, (*durationWrapper)(dst.(*time.Duration)))
 }
 
 type wrapNetIPNetScanPlan struct {
@@ -878,8 +792,8 @@ type wrapNetIPNetScanPlan struct {
 
 func (plan *wrapNetIPNetScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapNetIPNetScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapNetIPNetScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*netIPNetWrapper)(dst.(*net.IPNet)))
+	return plan.next.Scan(src, (*netIPNetWrapper)(dst.(*net.IPNet)))
 }
 
 type wrapNetIPScanPlan struct {
@@ -888,8 +802,8 @@ type wrapNetIPScanPlan struct {
 
 func (plan *wrapNetIPScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapNetIPScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapNetIPScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*netIPWrapper)(dst.(*net.IP)))
+	return plan.next.Scan(src, (*netIPWrapper)(dst.(*net.IP)))
 }
 
 type wrapMapStringToPointerStringScanPlan struct {
@@ -898,8 +812,8 @@ type wrapMapStringToPointerStringScanPlan struct {
 
 func (plan *wrapMapStringToPointerStringScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapMapStringToPointerStringScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapMapStringToPointerStringScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*mapStringToPointerStringWrapper)(dst.(*map[string]*string)))
+	return plan.next.Scan(src, (*mapStringToPointerStringWrapper)(dst.(*map[string]*string)))
 }
 
 type wrapMapStringToStringScanPlan struct {
@@ -908,8 +822,8 @@ type wrapMapStringToStringScanPlan struct {
 
 func (plan *wrapMapStringToStringScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapMapStringToStringScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapMapStringToStringScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*mapStringToStringWrapper)(dst.(*map[string]string)))
+	return plan.next.Scan(src, (*mapStringToStringWrapper)(dst.(*map[string]string)))
 }
 
 type wrapByte16ScanPlan struct {
@@ -918,8 +832,8 @@ type wrapByte16ScanPlan struct {
 
 func (plan *wrapByte16ScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapByte16ScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapByte16ScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*byte16Wrapper)(dst.(*[16]byte)))
+	return plan.next.Scan(src, (*byte16Wrapper)(dst.(*[16]byte)))
 }
 
 type wrapByteSliceScanPlan struct {
@@ -928,16 +842,19 @@ type wrapByteSliceScanPlan struct {
 
 func (plan *wrapByteSliceScanPlan) SetNext(next ScanPlan) { plan.next = next }
 
-func (plan *wrapByteSliceScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *wrapByteSliceScanPlan) Scan(src []byte, dst interface{}) error {
-	return plan.next.Scan(ci, oid, formatCode, src, (*byteSliceWrapper)(dst.(*[]byte)))
+	return plan.next.Scan(src, (*byteSliceWrapper)(dst.(*[]byte)))
 }
 
 type pointerEmptyInterfaceScanPlan struct {
-	codec Codec
+	codec      Codec
+	ci         *ConnInfo
+	oid        uint32
+	formatCode int16
 }
 
-func (plan *pointerEmptyInterfaceScanPlan) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (plan *pointerEmptyInterfaceScanPlan) Scan(src []byte, dst interface{}) error {
-	value, err := plan.codec.DecodeValue(ci, oid, formatCode, src)
+	value, err := plan.codec.DecodeValue(plan.ci, plan.oid, plan.formatCode, src)
 	if err != nil {
 		return err
 	}
@@ -948,45 +865,28 @@ func (plan *pointerEmptyInterfaceScanPlan) Scan(ci *ConnInfo, oid uint32, format
 	return nil
 }
 
-// PlanScan prepares a plan to scan a value into dst.
+// PlanScan prepares a plan to scan a value into target.
-func (ci *ConnInfo) PlanScan(oid uint32, formatCode int16, dst interface{}) ScanPlan {
+func (ci *ConnInfo) PlanScan(oid uint32, formatCode int16, target interface{}) ScanPlan {
-	if _, ok := dst.(*UndecodedBytes); ok {
+	if _, ok := target.(*UndecodedBytes); ok {
 		return scanPlanAnyToUndecodedBytes{}
 	}
 
 	switch formatCode {
 	case BinaryFormatCode:
-		switch dst.(type) {
+		switch target.(type) {
 		case *string:
 			switch oid {
 			case TextOID, VarcharOID:
 				return scanPlanString{}
 			}
-		case *int64:
-			if oid == Int8OID {
-				return scanPlanBinaryInt64{}
-			}
-		case *float32:
-			if oid == Float4OID {
-				return scanPlanBinaryFloat32{}
-			}
-		case *float64:
-			if oid == Float8OID {
-				return scanPlanBinaryFloat64{}
-			}
-		case *[]byte:
-			switch oid {
-			case ByteaOID, TextOID, VarcharOID, JSONOID:
-				return scanPlanBinaryBytes{}
-			}
 		}
 	case TextFormatCode:
-		switch dst.(type) {
+		switch target.(type) {
 		case *string:
 			return scanPlanString{}
 		case *[]byte:
 			if oid != ByteaOID {
-				return scanPlanBinaryBytes{}
+				return scanPlanAnyTextToBytes{}
 			}
 		case TextScanner:
 			return scanPlanTextAnyToTextScanner{}
@@ -995,47 +895,43 @@ func (ci *ConnInfo) PlanScan(oid uint32, formatCode int16, dst interface{}) Scan
 
 	var dt *DataType
 
-	if oid == 0 {
+	if dataType, ok := ci.DataTypeForOID(oid); ok {
-		if dataType, ok := ci.DataTypeForValue(dst); ok {
+		dt = dataType
-			dt = dataType
+	} else if dataType, ok := ci.DataTypeForValue(target); ok {
-			oid = dt.OID // Preserve assumed OID in case we are recursively called below.
+		dt = dataType
-		}
+		oid = dt.OID // Preserve assumed OID in case we are recursively called below.
-	} else {
-		if dataType, ok := ci.DataTypeForOID(oid); ok {
-			dt = dataType
-		}
 	}
 
 	if dt != nil {
-		if plan := dt.Codec.PlanScan(ci, oid, formatCode, dst, false); plan != nil {
+		if plan := dt.Codec.PlanScan(ci, oid, formatCode, target, false); plan != nil {
 			return plan
 		}
 
-		for _, f := range ci.TryWrapScanPlanFuncs {
+		if _, ok := target.(*interface{}); ok {
-			if wrapperPlan, nextDst, ok := f(dst); ok {
+			return &pointerEmptyInterfaceScanPlan{codec: dt.Codec, ci: ci, oid: oid, formatCode: formatCode}
-				if nextPlan := ci.PlanScan(oid, formatCode, nextDst); nextPlan != nil {
+		}
-					if _, ok := nextPlan.(scanPlanReflection); !ok { // avoid fallthrough -- this will go away when old system removed.
+
-						wrapperPlan.SetNext(nextPlan)
+		if _, ok := target.(sql.Scanner); ok {
-						return wrapperPlan
+			return &scanPlanCodecSQLScanner{c: dt.Codec, ci: ci, oid: oid, formatCode: formatCode}
-					}
+		}
+	}
+
+	for _, f := range ci.TryWrapScanPlanFuncs {
+		if wrapperPlan, nextDst, ok := f(target); ok {
+			if nextPlan := ci.PlanScan(oid, formatCode, nextDst); nextPlan != nil {
+				if _, failed := nextPlan.(*scanPlanFail); !failed {
+					wrapperPlan.SetNext(nextPlan)
+					return wrapperPlan
 				}
 			}
 		}
-
-		if _, ok := dst.(*interface{}); ok {
-			return &pointerEmptyInterfaceScanPlan{codec: dt.Codec}
-		}
-
-		if _, ok := dst.(sql.Scanner); ok {
-			return &scanPlanCodecSQLScanner{c: dt.Codec}
-		}
 	}
 
-	if _, ok := dst.(sql.Scanner); ok {
+	if _, ok := target.(sql.Scanner); ok {
-		return scanPlanSQLScanner{}
+		return &scanPlanSQLScanner{formatCode: formatCode}
 	}
 
-	return scanPlanReflection{}
+	return &scanPlanFail{oid: oid, formatCode: formatCode}
 }
 
 func (ci *ConnInfo) Scan(oid uint32, formatCode int16, src []byte, dst interface{}) error {
@@ -1044,7 +940,7 @@ func (ci *ConnInfo) Scan(oid uint32, formatCode int16, src []byte, dst interface
 	}
 
 	plan := ci.PlanScan(oid, formatCode, dst)
-	return plan.Scan(ci, oid, formatCode, src, dst)
+	return plan.Scan(src, dst)
 }
 
 func scanUnknownType(oid uint32, formatCode int16, buf []byte, dest interface{}) error {
@@ -1073,7 +969,7 @@ func codecScan(codec Codec, ci *ConnInfo, oid uint32, format int16, src []byte,
 	if scanPlan == nil {
 		return fmt.Errorf("PlanScan did not find a plan")
 	}
-	return scanPlan.Scan(ci, oid, format, src, dst)
+	return scanPlan.Scan(src, dst)
 }
 
 func codecDecodeToTextFormat(codec Codec, ci *ConnInfo, oid uint32, format int16, src []byte) (driver.Value, error) {

pgtype/pgtype_test.go

@@ -118,18 +118,10 @@ func TestConnInfoScanUnknownOIDToStringsAndBytes(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, []byte("foo"), b)
 
-	err = ci.Scan(unknownOID, pgx.BinaryFormatCode, srcBuf, &b)
-	assert.NoError(t, err)
-	assert.Equal(t, []byte("foo"), b)
-
 	var rb _byteSlice
 	err = ci.Scan(unknownOID, pgx.TextFormatCode, srcBuf, &rb)
 	assert.NoError(t, err)
 	assert.Equal(t, []byte("foo"), []byte(rb))
-
-	err = ci.Scan(unknownOID, pgx.BinaryFormatCode, srcBuf, &b)
-	assert.NoError(t, err)
-	assert.Equal(t, []byte("foo"), []byte(rb))
 }
 
 type pgCustomType struct {
@@ -219,21 +211,6 @@ func BenchmarkConnInfoScanInt4IntoBinaryDecoder(b *testing.B) {
 	}
 }
 
-func TestScanPlanBinaryInt32ScanChangedType(t *testing.T) {
-	ci := pgtype.NewConnInfo()
-	src := []byte{0, 0, 0, 42}
-	var v int32
-
-	plan := ci.PlanScan(pgtype.Int4OID, pgtype.BinaryFormatCode, &v)
-	err := plan.Scan(ci, pgtype.Int4OID, pgtype.BinaryFormatCode, src, &v)
-	require.NoError(t, err)
-	require.EqualValues(t, 42, v)
-
-	var d pgtype.Int4
-	err = plan.Scan(ci, pgtype.Int4OID, pgtype.BinaryFormatCode, src, &d)
-	require.EqualError(t, err, pgtype.ErrScanTargetTypeChanged.Error())
-}
-
 func BenchmarkConnInfoScanInt4IntoGoInt32(b *testing.B) {
 	ci := pgtype.NewConnInfo()
 	src := []byte{0, 0, 0, 42}
@@ -260,7 +237,7 @@ func BenchmarkScanPlanScanInt4IntoBinaryDecoder(b *testing.B) {
 
 	for i := 0; i < b.N; i++ {
 		v = pgtype.Int4{}
-		err := plan.Scan(ci, pgtype.Int4OID, pgtype.BinaryFormatCode, src, &v)
+		err := plan.Scan(src, &v)
 		if err != nil {
 			b.Fatal(err)
 		}
@@ -279,7 +256,7 @@ func BenchmarkScanPlanScanInt4IntoGoInt32(b *testing.B) {
 
 	for i := 0; i < b.N; i++ {
 		v = 0
-		err := plan.Scan(ci, pgtype.Int4OID, pgtype.BinaryFormatCode, src, &v)
+		err := plan.Scan(src, &v)
 		if err != nil {
 			b.Fatal(err)
 		}

pgtype/point.go

@@ -77,7 +77,7 @@ func (dst *Point) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToPointScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), dst)
+		return scanPlanTextAnyToPointScanner{}.Scan([]byte(src), dst)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -214,7 +214,7 @@ func (c PointCodec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []by
 
 type scanPlanBinaryPointToPointScanner struct{}
 
-func (scanPlanBinaryPointToPointScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryPointToPointScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(PointScanner)
 
 	if src == nil {
@@ -236,7 +236,7 @@ func (scanPlanBinaryPointToPointScanner) Scan(ci *ConnInfo, oid uint32, formatCo
 
 type scanPlanTextAnyToPointScanner struct{}
 
-func (scanPlanTextAnyToPointScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToPointScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(PointScanner)
 
 	if src == nil {

pgtype/polygon.go

@@ -42,7 +42,7 @@ func (p *Polygon) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToPolygonScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), p)
+		return scanPlanTextAnyToPolygonScanner{}.Scan([]byte(src), p)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -158,7 +158,7 @@ func (PolygonCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target inte
 
 type scanPlanBinaryPolygonToPolygonScanner struct{}
 
-func (scanPlanBinaryPolygonToPolygonScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryPolygonToPolygonScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(PolygonScanner)
 
 	if src == nil {
@@ -193,7 +193,7 @@ func (scanPlanBinaryPolygonToPolygonScanner) Scan(ci *ConnInfo, oid uint32, form
 
 type scanPlanTextAnyToPolygonScanner struct{}
 
-func (scanPlanTextAnyToPolygonScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToPolygonScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(PolygonScanner)
 
 	if src == nil {

pgtype/qchar.go

@@ -72,7 +72,7 @@ func (QCharCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interf
 
 type scanPlanQcharCodecByte struct{}
 
-func (scanPlanQcharCodecByte) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanQcharCodecByte) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -94,7 +94,7 @@ func (scanPlanQcharCodecByte) Scan(ci *ConnInfo, oid uint32, formatCode int16, s
 
 type scanPlanQcharCodecRune struct{}
 
-func (scanPlanQcharCodecRune) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanQcharCodecRune) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}

pgtype/text.go

@@ -189,7 +189,7 @@ func (c TextCodec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []byt
 
 type scanPlanTextAnyToString struct{}
 
-func (scanPlanTextAnyToString) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToString) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -202,7 +202,7 @@ func (scanPlanTextAnyToString) Scan(ci *ConnInfo, oid uint32, formatCode int16,
 
 type scanPlanAnyToNewByteSlice struct{}
 
-func (scanPlanAnyToNewByteSlice) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanAnyToNewByteSlice) Scan(src []byte, dst interface{}) error {
 	p := (dst).(*[]byte)
 	if src == nil {
 		*p = nil
@@ -216,7 +216,7 @@ func (scanPlanAnyToNewByteSlice) Scan(ci *ConnInfo, oid uint32, formatCode int16
 
 type scanPlanTextAnyToRune struct{}
 
-func (scanPlanTextAnyToRune) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToRune) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -234,7 +234,7 @@ func (scanPlanTextAnyToRune) Scan(ci *ConnInfo, oid uint32, formatCode int16, sr
 
 type scanPlanTextAnyToTextScanner struct{}
 
-func (scanPlanTextAnyToTextScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToTextScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TextScanner)
 
 	if src == nil {

pgtype/tid.go

@@ -53,7 +53,7 @@ func (dst *TID) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToTIDScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), dst)
+		return scanPlanTextAnyToTIDScanner{}.Scan([]byte(src), dst)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -152,7 +152,7 @@ func (TIDCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfac
 
 type scanPlanBinaryTIDToTIDScanner struct{}
 
-func (scanPlanBinaryTIDToTIDScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryTIDToTIDScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TIDScanner)
 
 	if src == nil {
@@ -172,7 +172,7 @@ func (scanPlanBinaryTIDToTIDScanner) Scan(ci *ConnInfo, oid uint32, formatCode i
 
 type scanPlanBinaryTIDToTextScanner struct{}
 
-func (scanPlanBinaryTIDToTextScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryTIDToTextScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TextScanner)
 
 	if src == nil {
@@ -194,7 +194,7 @@ func (scanPlanBinaryTIDToTextScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToTIDScanner struct{}
 
-func (scanPlanTextAnyToTIDScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToTIDScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TIDScanner)
 
 	if src == nil {

pgtype/time.go

@@ -45,7 +45,7 @@ func (t *Time) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextAnyToTimeScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), t)
+		return scanPlanTextAnyToTimeScanner{}.Scan([]byte(src), t)
 	}
 
 	return fmt.Errorf("cannot scan %T", src)
@@ -149,7 +149,7 @@ func (TimeCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfa
 
 type scanPlanBinaryTimeToTimeScanner struct{}
 
-func (scanPlanBinaryTimeToTimeScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryTimeToTimeScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TimeScanner)
 
 	if src == nil {
@@ -167,7 +167,7 @@ func (scanPlanBinaryTimeToTimeScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToTimeScanner struct{}
 
-func (scanPlanTextAnyToTimeScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToTimeScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TimeScanner)
 
 	if src == nil {

pgtype/timestamp.go

@@ -44,7 +44,7 @@ func (ts *Timestamp) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextTimestampToTimestampScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), ts)
+		return scanPlanTextTimestampToTimestampScanner{}.Scan([]byte(src), ts)
 	case time.Time:
 		*ts = Timestamp{Time: src, Valid: true}
 		return nil
@@ -172,7 +172,7 @@ func (TimestampCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target in
 
 type scanPlanBinaryTimestampToTimestampScanner struct{}
 
-func (scanPlanBinaryTimestampToTimestampScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryTimestampToTimestampScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TimestampScanner)
 
 	if src == nil {
@@ -204,7 +204,7 @@ func (scanPlanBinaryTimestampToTimestampScanner) Scan(ci *ConnInfo, oid uint32,
 
 type scanPlanTextTimestampToTimestampScanner struct{}
 
-func (scanPlanTextTimestampToTimestampScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextTimestampToTimestampScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TimestampScanner)
 
 	if src == nil {

pgtype/timestamp_test.go

@@ -52,6 +52,6 @@ func TestTimestampCodecDecodeTextInvalid(t *testing.T) {
 	c := &pgtype.TimestampCodec{}
 	var ts pgtype.Timestamp
 	plan := c.PlanScan(nil, pgtype.TimestampOID, pgtype.TextFormatCode, &ts, false)
-	err := plan.Scan(nil, pgtype.TimestampOID, pgtype.TextFormatCode, []byte(`eeeee`), &ts)
+	err := plan.Scan([]byte(`eeeee`), &ts)
 	require.Error(t, err)
 }

pgtype/timestamptz.go

@@ -53,7 +53,7 @@ func (tstz *Timestamptz) Scan(src interface{}) error {
 
 	switch src := src.(type) {
 	case string:
-		return scanPlanTextTimestamptzToTimestamptzScanner{}.Scan(nil, 0, TextFormatCode, []byte(src), tstz)
+		return scanPlanTextTimestamptzToTimestamptzScanner{}.Scan([]byte(src), tstz)
 	case time.Time:
 		*tstz = Timestamptz{Time: src, Valid: true}
 		return nil
@@ -220,7 +220,7 @@ func (TimestamptzCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target
 
 type scanPlanBinaryTimestamptzToTimestamptzScanner struct{}
 
-func (scanPlanBinaryTimestamptzToTimestamptzScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryTimestamptzToTimestamptzScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TimestamptzScanner)
 
 	if src == nil {
@@ -252,7 +252,7 @@ func (scanPlanBinaryTimestamptzToTimestamptzScanner) Scan(ci *ConnInfo, oid uint
 
 type scanPlanTextTimestamptzToTimestamptzScanner struct{}
 
-func (scanPlanTextTimestamptzToTimestamptzScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextTimestamptzToTimestamptzScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(TimestamptzScanner)
 
 	if src == nil {

pgtype/timestamptz_test.go

@@ -52,7 +52,7 @@ func TestTimestamptzDecodeTextInvalid(t *testing.T) {
 	c := &pgtype.TimestamptzCodec{}
 	var tstz pgtype.Timestamptz
 	plan := c.PlanScan(nil, pgtype.TimestamptzOID, pgtype.TextFormatCode, &tstz, false)
-	err := plan.Scan(nil, pgtype.TimestamptzOID, pgtype.TextFormatCode, []byte(`eeeee`), &tstz)
+	err := plan.Scan([]byte(`eeeee`), &tstz)
 	require.Error(t, err)
 }
 

pgtype/uint32.go

@@ -246,7 +246,7 @@ func (c Uint32Codec) DecodeValue(ci *ConnInfo, oid uint32, format int16, src []b
 
 type scanPlanBinaryUint32ToUint32 struct{}
 
-func (scanPlanBinaryUint32ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryUint32ToUint32) Scan(src []byte, dst interface{}) error {
 	if src == nil {
 		return fmt.Errorf("cannot scan null into %T", dst)
 	}
@@ -263,7 +263,7 @@ func (scanPlanBinaryUint32ToUint32) Scan(ci *ConnInfo, oid uint32, formatCode in
 
 type scanPlanBinaryUint32ToUint32Scanner struct{}
 
-func (scanPlanBinaryUint32ToUint32Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryUint32ToUint32Scanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(Uint32Scanner)
 	if !ok {
 		return ErrScanTargetTypeChanged
@@ -284,7 +284,7 @@ func (scanPlanBinaryUint32ToUint32Scanner) Scan(ci *ConnInfo, oid uint32, format
 
 type scanPlanTextAnyToUint32Scanner struct{}
 
-func (scanPlanTextAnyToUint32Scanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToUint32Scanner) Scan(src []byte, dst interface{}) error {
 	s, ok := (dst).(Uint32Scanner)
 	if !ok {
 		return ErrScanTargetTypeChanged

pgtype/uuid.go

@@ -186,7 +186,7 @@ func (UUIDCodec) PlanScan(ci *ConnInfo, oid uint32, format int16, target interfa
 
 type scanPlanBinaryUUIDToUUIDScanner struct{}
 
-func (scanPlanBinaryUUIDToUUIDScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanBinaryUUIDToUUIDScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(UUIDScanner)
 
 	if src == nil {
@@ -205,7 +205,7 @@ func (scanPlanBinaryUUIDToUUIDScanner) Scan(ci *ConnInfo, oid uint32, formatCode
 
 type scanPlanTextAnyToUUIDScanner struct{}
 
-func (scanPlanTextAnyToUUIDScanner) Scan(ci *ConnInfo, oid uint32, formatCode int16, src []byte, dst interface{}) error {
+func (scanPlanTextAnyToUUIDScanner) Scan(src []byte, dst interface{}) error {
 	scanner := (dst).(UUIDScanner)
 
 	if src == nil {

rows.go

@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"fmt"
+	"reflect"
 	"time"
 
 	"github.com/jackc/pgproto3/v2"
@@ -111,6 +112,7 @@ type connRows struct {
 	multiResultReader *pgconn.MultiResultReader
 
 	scanPlans []pgtype.ScanPlan
+	scanTypes []reflect.Type
 }
 
 func (rows *connRows) FieldDescriptions() []pgproto3.FieldDescription {
@@ -208,8 +210,10 @@ func (rows *connRows) Scan(dest ...interface{}) error {
 
 	if rows.scanPlans == nil {
 		rows.scanPlans = make([]pgtype.ScanPlan, len(values))
+		rows.scanTypes = make([]reflect.Type, len(values))
 		for i := range dest {
 			rows.scanPlans[i] = ci.PlanScan(fieldDescriptions[i].DataTypeOID, fieldDescriptions[i].Format, dest[i])
+			rows.scanTypes[i] = reflect.TypeOf(dest[i])
 		}
 	}
 
@@ -218,7 +222,12 @@ func (rows *connRows) Scan(dest ...interface{}) error {
 			continue
 		}
 
-		err := rows.scanPlans[i].Scan(ci, fieldDescriptions[i].DataTypeOID, fieldDescriptions[i].Format, values[i], dst)
+		if rows.scanTypes[i] != reflect.TypeOf(dst) {
+			rows.scanPlans[i] = ci.PlanScan(fieldDescriptions[i].DataTypeOID, fieldDescriptions[i].Format, dest[i])
+			rows.scanTypes[i] = reflect.TypeOf(dest[i])
+		}
+
+		err := rows.scanPlans[i].Scan(values[i], dst)
 		if err != nil {
 			err = ScanArgError{ColumnIndex: i, Err: err}
 			rows.fatal(err)

stdlib/sql.go

@@ -605,21 +605,21 @@ func (r *Rows) Next(dest []driver.Value) error {
 				var d bool
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					return d, err
 				}
 			case pgtype.ByteaOID:
 				var d []byte
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					return d, err
 				}
 			case pgtype.CIDOID, pgtype.OIDOID, pgtype.XIDOID:
 				var d pgtype.Uint32
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					if err != nil {
 						return nil, err
 					}
@@ -629,7 +629,7 @@ func (r *Rows) Next(dest []driver.Value) error {
 				var d pgtype.Date
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					if err != nil {
 						return nil, err
 					}
@@ -639,42 +639,42 @@ func (r *Rows) Next(dest []driver.Value) error {
 				var d float32
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					return float64(d), err
 				}
 			case pgtype.Float8OID:
 				var d float64
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					return d, err
 				}
 			case pgtype.Int2OID:
 				var d int16
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					return int64(d), err
 				}
 			case pgtype.Int4OID:
 				var d int32
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					return int64(d), err
 				}
 			case pgtype.Int8OID:
 				var d int64
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					return d, err
 				}
 			case pgtype.JSONOID, pgtype.JSONBOID:
 				var d []byte
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					if err != nil {
 						return nil, err
 					}
@@ -684,7 +684,7 @@ func (r *Rows) Next(dest []driver.Value) error {
 				var d pgtype.Timestamp
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					if err != nil {
 						return nil, err
 					}
@@ -694,7 +694,7 @@ func (r *Rows) Next(dest []driver.Value) error {
 				var d pgtype.Timestamptz
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					if err != nil {
 						return nil, err
 					}
@@ -704,7 +704,7 @@ func (r *Rows) Next(dest []driver.Value) error {
 				var d string
 				scanPlan := ci.PlanScan(dataTypeOID, format, &d)
 				r.valueFuncs[i] = func(src []byte) (driver.Value, error) {
-					err := scanPlan.Scan(ci, dataTypeOID, format, src, &d)
+					err := scanPlan.Scan(src, &d)
 					return d, err
 				}
 			}