Use binary encoding for bool

bench_test.go

@@ -13,6 +13,7 @@ var int4TextVsBinaryTestDataLoaded bool
 var int8TextVsBinaryTestDataLoaded bool
 var float4TextVsBinaryTestDataLoaded bool
 var float8TextVsBinaryTestDataLoaded bool
+var boolTextVsBinaryTestDataLoaded bool
 
 func mustPrepare(b *testing.B, conn *Connection, name, sql string) {
 	if err := conn.Prepare(name, sql); err != nil {
@@ -529,3 +530,63 @@ func BenchmarkFloat8Binary(b *testing.B) {
 		}
 	}
 }
+
+func createBoolTextVsBinaryTestData(b *testing.B, conn *Connection) {
+	if boolTextVsBinaryTestDataLoaded {
+		return
+	}
+
+	if _, err := conn.Execute(`
+		drop table if exists t;
+
+		create temporary table t(
+			a bool not null,
+			b bool not null,
+			c bool not null,
+			d bool not null,
+			e bool not null
+		);
+
+		insert into t(a, b, c, d, e)
+		select
+			random() > 0.5, random() > 0.5, random() > 0.5, random() > 0.5, random() > 0.5
+		from generate_series(1, 10);
+	`); err != nil {
+		b.Fatalf("Could not set up test data: %v", err)
+	}
+
+	boolTextVsBinaryTestDataLoaded = true
+}
+
+func BenchmarkBoolText(b *testing.B) {
+	conn := getSharedConnection()
+	createBoolTextVsBinaryTestData(b, conn)
+
+	binaryDecoder := valueTranscoders[oid(16)].DecodeBinary
+	valueTranscoders[oid(16)].DecodeBinary = nil
+	defer func() { valueTranscoders[oid(16)].DecodeBinary = binaryDecoder }()
+
+	mustPrepare(b, conn, "selectBool", "select * from t")
+	defer func() { conn.Deallocate("selectBool") }()
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if _, err := conn.SelectRows("selectBool"); err != nil {
+			b.Fatalf("Failure while benchmarking: %v", err)
+		}
+	}
+}
+
+func BenchmarkBoolBinary(b *testing.B) {
+	conn := getSharedConnection()
+	createBoolTextVsBinaryTestData(b, conn)
+	mustPrepare(b, conn, "selectBool", "select * from t")
+	defer func() { conn.Deallocate("selectBool") }()
+
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		if _, err := conn.SelectRows("selectBool"); err != nil {
+			b.Fatalf("Failure while benchmarking: %v", err)
+		}
+	}
+}

value_transcoder.go

@@ -22,8 +22,10 @@ func init() {
 
 	// bool
 	valueTranscoders[oid(16)] = &valueTranscoder{
-		DecodeText: decodeBoolFromText,
+		DecodeText:   decodeBoolFromText,
-		EncodeTo:   encodeBool}
+		DecodeBinary: decodeBoolFromBinary,
+		EncodeTo:     encodeBool,
+		EncodeFormat: 1}
 
 	// bytea
 	valueTranscoders[oid(17)] = &valueTranscoder{
@@ -90,11 +92,22 @@ func decodeBoolFromText(mr *MessageReader, size int32) interface{} {
 	}
 }
 
+func decodeBoolFromBinary(mr *MessageReader, size int32) interface{} {
+	if size != 1 {
+		panic("Received an invalid size for an bool")
+	}
+	b := mr.ReadByte()
+	return b != 0
+}
+
 func encodeBool(w *messageWriter, value interface{}) {
 	v := value.(bool)
-	s := strconv.FormatBool(v)
+	w.write(int32(1))
-	w.write(int32(len(s)))
+	if v {
-	w.writeString(s)
+		w.writeByte(1)
+	} else {
+		w.writeByte(0)
+	}
 }
 
 func decodeInt8FromText(mr *MessageReader, size int32) interface{} {