fix: use BLOB sql type to encode []byte in MySQL and SQLite

dialect/pgdialect/sqltype.go

@@ -68,6 +68,10 @@ func fieldSQLType(field *schema.Field) string {
 		}
 	}
 
+	if field.DiscoveredSQLType == sqltype.Blob {
+		return pgTypeBytea
+	}
+
 	return sqlType(field.IndirectType)
 }
 

dialect/sqlitedialect/dialect.go

@@ -2,6 +2,7 @@ package sqlitedialect
 
 import (
 	"database/sql"
+	"encoding/hex"
 
 	"github.com/uptrace/bun/dialect"
 	"github.com/uptrace/bun/dialect/feature"
@@ -47,14 +48,36 @@ func (d *Dialect) OnTable(table *schema.Table) {
 }
 
 func (d *Dialect) onField(field *schema.Field) {
-	// INTEGER PRIMARY KEY is an alias for the ROWID.
-	// It is safe to convert all ints to INTEGER, because SQLite types don't have size.
-	switch field.DiscoveredSQLType {
-	case sqltype.SmallInt, sqltype.BigInt:
-		field.DiscoveredSQLType = sqltype.Integer
-	}
+	field.DiscoveredSQLType = fieldSQLType(field)
 }
 
 func (d *Dialect) IdentQuote() byte {
 	return '"'
 }
+
+func (d *Dialect) AppendBytes(b []byte, bs []byte) []byte {
+	if bs == nil {
+		return dialect.AppendNull(b)
+	}
+
+	b = append(b, `X'`...)
+
+	s := len(b)
+	b = append(b, make([]byte, hex.EncodedLen(len(bs)))...)
+	hex.Encode(b[s:], bs)
+
+	b = append(b, '\'')
+
+	return b
+}
+
+func fieldSQLType(field *schema.Field) string {
+	switch field.DiscoveredSQLType {
+	case sqltype.SmallInt, sqltype.BigInt:
+		// INTEGER PRIMARY KEY is an alias for the ROWID.
+		// It is safe to convert all ints to INTEGER, because SQLite types don't have size.
+		return sqltype.Integer
+	default:
+		return field.DiscoveredSQLType
+	}
+}

dialect/sqltype/sqltype.go

@@ -8,6 +8,7 @@ const (
 	Real            = "REAL"
 	DoublePrecision = "DOUBLE PRECISION"
 	VarChar         = "VARCHAR"
+	Blob            = "BLOB"
 	Timestamp       = "TIMESTAMP"
 	JSON            = "JSON"
 	JSONB           = "JSONB"

internal/dbtest/db_test.go

@@ -227,11 +227,12 @@ func TestDB(t *testing.T) {
 		{testFKViolation},
 		{testInterfaceAny},
 		{testInterfaceJSON},
-		{testScanBytes},
+		{testScanRawMessage},
 		{testPointers},
 		{testExists},
 		{testScanTimeIntoString},
 		{testModelNonPointer},
+		{testBinaryData},
 	}
 
 	testEachDB(t, func(t *testing.T, dbName string, db *bun.DB) {
@@ -828,7 +829,7 @@ func testInterfaceJSON(t *testing.T, db *bun.DB) {
 	require.Equal(t, "hello", model.Value)
 }
 
-func testScanBytes(t *testing.T, db *bun.DB) {
+func testScanRawMessage(t *testing.T, db *bun.DB) {
 	type Model struct {
 		ID    int64
 		Value json.RawMessage
@@ -914,3 +915,23 @@ func testModelNonPointer(t *testing.T, db *bun.DB) {
 	require.Error(t, err)
 	require.Equal(t, "bun: Model(non-pointer dbtest_test.Model)", err.Error())
 }
+
+func testBinaryData(t *testing.T, db *bun.DB) {
+	type Model struct {
+		ID   int64
+		Data []byte
+	}
+
+	ctx := context.Background()
+
+	err := db.ResetModel(ctx, (*Model)(nil))
+	require.NoError(t, err)
+
+	_, err = db.NewInsert().Model(&Model{Data: []byte("hello")}).Exec(ctx)
+	require.NoError(t, err)
+
+	var model Model
+	err = db.NewSelect().Model(&model).Scan(ctx)
+	require.NoError(t, err)
+	require.Equal(t, []byte("hello"), model.Data)
+}

internal/dbtest/testdata/snapshots/TestQuery-sqlite-60

@@ -1 +1 @@
-INSERT INTO "models" ("bytes") VALUES ('\x00000000000000000000')
+INSERT INTO "models" ("bytes") VALUES (X'00000000000000000000')

schema/sqltype.go

@@ -61,6 +61,14 @@ func DiscoverSQLType(typ reflect.Type) string {
 	case nullStringType:
 		return sqltype.VarChar
 	}
+
+	switch typ.Kind() {
+	case reflect.Slice:
+		if typ.Elem().Kind() == reflect.Uint8 {
+			return sqltype.Blob
+		}
+	}
+
 	return sqlTypes[typ.Kind()]
 }