optimize unit test & add document

tools/goctl/model/sql/gen/new.go

@@ -5,10 +5,11 @@ import (
 	"github.com/tal-tech/go-zero/tools/goctl/util/templatex"
 )
 
-func genNew(table Table) (string, error) {
+func genNew(table Table, withCache bool) (string, error) {
 	output, err := templatex.With("new").
 		Parse(template.New).
 		Execute(map[string]interface{}{
+			"withCache":             withCache,
 			"upperStartCamelObject": table.Name.Snake2Camel(),
 		})
 	if err != nil {