fix bit type on postgres

dialect_postgres.go

@@ -781,6 +781,9 @@ func (db *postgres) SqlType(c *core.Column) string {
 	case core.TinyInt:
 		res = core.SmallInt
 		return res
+	case core.Bit:
+		res = core.Boolean
+		return res
 	case core.MediumInt, core.Int, core.Integer:
 		if c.IsAutoIncrement {
 			return core.Serial

session_query_test.go

@@ -65,7 +65,7 @@ func TestQueryString2(t *testing.T) {
 	assert.Equal(t, 1, len(records))
 	assert.Equal(t, 2, len(records[0]))
 	assert.Equal(t, "1", records[0]["id"])
-	assert.Equal(t, "0", records[0]["msg"])
+	assert.True(t, "0" == records[0]["msg"] || "false" == records[0]["msg"])
 }
 
 func toString(i interface{}) string {