refactor/mssql: change default sizing of binary columns to max

dialect_mssql.go

@@ -232,10 +232,10 @@ func (db *mssql) SqlType(c *core.Column) string {
 		c.IsPrimaryKey = true
 		c.Nullable = false
 		res = core.BigInt
-	case core.Bytea, core.Blob, core.Binary, core.TinyBlob, core.MediumBlob, core.LongBlob:
+	case core.VarBinary, core.Bytea, core.Blob, core.Binary, core.TinyBlob, core.MediumBlob, core.LongBlob:
 		res = core.VarBinary
 		if c.Length == 0 {
-			c.Length = 50
+			res += "(MAX)"
 		}
 	case core.TimeStamp:
 		res = core.DateTime

types_test.go

@@ -9,8 +9,8 @@ import (
 	"fmt"
 	"testing"
 
-	"xorm.io/core"
 	"github.com/stretchr/testify/assert"
+	"xorm.io/core"
 )
 
 func TestArrayField(t *testing.T) {
@@ -99,6 +99,29 @@ func TestGetBytes(t *testing.T) {
 	assert.Equal(t, "test", string(b.Data))
 }
 
+func TestGetBytesMax(t *testing.T) {
+	assert.NoError(t, prepareEngine())
+
+	type Varbinary struct {
+		Data []byte `xorm:"VARBINARY"`
+	}
+
+	err := testEngine.Sync2(new(Varbinary))
+	assert.NoError(t, err)
+
+	cnt, err := testEngine.Insert(&Varbinary{
+		Data: []byte("test"),
+	})
+	assert.NoError(t, err)
+	assert.EqualValues(t, 1, cnt)
+
+	var b Varbinary
+	has, err := testEngine.Get(&b)
+	assert.NoError(t, err)
+	assert.Equal(t, true, has)
+	assert.Equal(t, "test", string(b.Data))
+}
+
 type ConvString string
 
 func (s *ConvString) FromDB(data []byte) error {