diff --git a/query_test.go b/query_test.go
index 9e31a009..439d808a 100644
--- a/query_test.go
+++ b/query_test.go
@@ -453,7 +453,7 @@ func TestQueryRowErrors(t *testing.T) {
 		{"select $1", []interface{}{"Jack"}, []interface{}{&actual.i16}, "could not determine data type of parameter $1 (SQLSTATE 42P18)"},
 		{"select $1::badtype", []interface{}{"Jack"}, []interface{}{&actual.i16}, `type "badtype" does not exist`},
 		{"SYNTAX ERROR", []interface{}{}, []interface{}{&actual.i16}, "SQLSTATE 42601"},
-		{"select $1::text", []interface{}{"Jack"}, []interface{}{&actual.i16}, "Expected type oid 21 but received type oid 25"},
+		{"select $1::text", []interface{}{"Jack"}, []interface{}{&actual.i16}, "Cannot decode oid 25 into int16"},
 		{"select $1::int8range", []interface{}{int(705)}, []interface{}{&actual.s}, "Cannot encode int into oid 3926 - int must implement Encoder or be converted to a string"},
 	}
 
diff --git a/values.go b/values.go
index cd2c4e09..71185999 100644
--- a/values.go
+++ b/values.go
@@ -418,6 +418,11 @@ func decodeBool(vr *ValueReader) bool {
 		return false
 	}
 
+	if vr.Type().DataType != BoolOid {
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into bool", vr.Type().DataType)))
+		return false
+	}
+
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
 		s := vr.ReadString(vr.Len())
@@ -468,7 +473,7 @@ func decodeInt8(vr *ValueReader) int64 {
 	}
 
 	if vr.Type().DataType != Int8Oid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int8Oid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into int8", vr.Type().DataType)))
 		return 0
 	}
 
@@ -534,7 +539,7 @@ func decodeInt2(vr *ValueReader) int16 {
 	}
 
 	if vr.Type().DataType != Int2Oid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int2Oid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into int16", vr.Type().DataType)))
 		return 0
 	}
 
@@ -615,7 +620,7 @@ func decodeInt4(vr *ValueReader) int32 {
 	}
 
 	if vr.Type().DataType != Int4Oid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int4Oid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into int32", vr.Type().DataType)))
 		return 0
 	}
 
@@ -689,7 +694,7 @@ func decodeOid(vr *ValueReader) Oid {
 	}
 
 	if vr.Type().DataType != OidOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", OidOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into pgx.Oid", vr.Type().DataType)))
 		return 0
 	}
 
@@ -731,6 +736,11 @@ func decodeFloat4(vr *ValueReader) float32 {
 		return 0
 	}
 
+	if vr.Type().DataType != Float4Oid {
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into float32", vr.Type().DataType)))
+		return 0
+	}
+
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
 		s := vr.ReadString(vr.Len())
@@ -783,6 +793,11 @@ func decodeFloat8(vr *ValueReader) float64 {
 		return 0
 	}
 
+	if vr.Type().DataType != Float8Oid {
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into float64", vr.Type().DataType)))
+		return 0
+	}
+
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
 		s := vr.ReadString(vr.Len())
@@ -852,6 +867,11 @@ func decodeBytea(vr *ValueReader) []byte {
 		return nil
 	}
 
+	if vr.Type().DataType != ByteaOid {
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into []byte", vr.Type().DataType)))
+		return nil
+	}
+
 	switch vr.Type().FormatCode {
 	case TextFormatCode:
 		s := vr.ReadString(vr.Len())
@@ -890,7 +910,7 @@ func decodeDate(vr *ValueReader) time.Time {
 	}
 
 	if vr.Type().DataType != DateOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", DateOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into time.Time", vr.Type().DataType)))
 		return zeroTime
 	}
 
@@ -936,7 +956,7 @@ func decodeTimestampTz(vr *ValueReader) time.Time {
 	}
 
 	if vr.Type().DataType != TimestampTzOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", TimestampTzOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into time.Time", vr.Type().DataType)))
 		return zeroTime
 	}
 
@@ -986,7 +1006,7 @@ func decodeTimestamp(vr *ValueReader) time.Time {
 	}
 
 	if vr.Type().DataType != TimestampOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", TimestampOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into time.Time", vr.Type().DataType)))
 		return zeroTime
 	}
 
@@ -1048,7 +1068,7 @@ func decodeInt2Array(vr *ValueReader) []int16 {
 	}
 
 	if vr.Type().DataType != Int2ArrayOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int2ArrayOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into []int16", vr.Type().DataType)))
 		return nil
 	}
 
@@ -1110,7 +1130,7 @@ func decodeInt4Array(vr *ValueReader) []int32 {
 	}
 
 	if vr.Type().DataType != Int4ArrayOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int4ArrayOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into []int32", vr.Type().DataType)))
 		return nil
 	}
 
@@ -1172,7 +1192,7 @@ func decodeInt8Array(vr *ValueReader) []int64 {
 	}
 
 	if vr.Type().DataType != Int8ArrayOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Int8ArrayOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into []int64", vr.Type().DataType)))
 		return nil
 	}
 
@@ -1234,7 +1254,7 @@ func decodeFloat4Array(vr *ValueReader) []float32 {
 	}
 
 	if vr.Type().DataType != Float4ArrayOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Float4ArrayOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into []float32", vr.Type().DataType)))
 		return nil
 	}
 
@@ -1300,7 +1320,7 @@ func decodeFloat8Array(vr *ValueReader) []float64 {
 	}
 
 	if vr.Type().DataType != Float8ArrayOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v but received type oid %v", Float8ArrayOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into []float64", vr.Type().DataType)))
 		return nil
 	}
 
@@ -1366,7 +1386,7 @@ func decodeTextArray(vr *ValueReader) []string {
 	}
 
 	if vr.Type().DataType != TextArrayOid && vr.Type().DataType != VarcharArrayOid {
-		vr.Fatal(ProtocolError(fmt.Sprintf("Expected type oid %v or %v but received type oid %v", TextArrayOid, VarcharArrayOid, vr.Type().DataType)))
+		vr.Fatal(ProtocolError(fmt.Sprintf("Cannot decode oid %v into []string", vr.Type().DataType)))
 		return nil
 	}