// sqlserver driver treats NULL and 'NULL' the same
		t.Skip("skip sqlserver")
	}

	type NullModel struct {
		ID      uint
		Content string `gorm:"default:null"`
	}

	type NullStringModel struct {
		ID      uint
		Content string `gorm:"default:'null'"`
		Active  bool   `gorm:"default:false"`
	}

	tableName := "null_string_model"

		// these dialects do not support the "returning" clause
		return
	default:
		// This user struct will leverage the existing users table, but override
		// the Name field to default to null.
		type user struct {
			gorm.Model
			Name string `gorm:"default:null"`
		}
		u1 := user{}

		if results := DB.Create(&u1); results.Error != nil {
			t.Fatalf("errors happened on create: %v", results.Error)
		} else if results.RowsAffected != 1 {

						if v, ok := selectColumns[field.DBName]; (ok && v) || (!ok && !restricted) {
							if !field.PrimaryKey && (!field.HasDefaultValue || field.DefaultValueInterface != nil ||
								strings.EqualFold(field.DefaultValue, "NULL")) && field.AutoCreateTime == 0 {
								if field.AutoUpdateTime > 0 {
									assignment := clause.Assignment{Column: clause.Column{Name: field.DBName}, Value: curTime}
									switch field.AutoUpdateTime {

// value includes a deleted_at field, then Delete performs a soft delete instead by setting deleted_at with the current
// time if null.
func (db *DB) Delete(value interface{}, conds ...interface{}) (tx *DB) {
	tx = db.getInstance()
	if len(conds) > 0 {
		if exprs := tx.Statement.BuildCondition(conds[0], conds[1:]...); len(exprs) > 0 {

	}

	dryDB := DB.Session(&gorm.Session{DryRun: true})
	stmt := dryDB.Save(&user).Statement
	if !regexp.MustCompile(`.users.\..deleted_at. IS NULL`).MatchString(stmt.SQL.String()) {
		t.Fatalf("invalid updating SQL, got %v", stmt.SQL.String())
	}

	dryDB = DB.Session(&gorm.Session{DryRun: true})
	stmt = dryDB.Unscoped().Save(&user).Statement

}

func TestBelongsToDefaultValue(t *testing.T) {
	type Org struct {
		ID string
	}
	type BelongsToUser struct {
		OrgID string
		Org   Org `gorm:"default:NULL"`
	}

	tx := DB.Session(&gorm.Session{})
	tx.Config.DisableForeignKeyConstraintWhenMigrating = true
	AssertEqual(t, DB.Config.DisableForeignKeyConstraintWhenMigrating, false)

			stmt.DB.Dialector.BindVarTo(writer, stmt, v)
		case []interface{}:
			if len(v) > 0 {
				writer.WriteByte('(')
				stmt.AddVar(writer, v...)
				writer.WriteByte(')')
			} else {
				writer.WriteString("(NULL)")
			}
		case *DB:
			subdb := v.Session(&Session{Logger: logger.Discard, DryRun: true}).getInstance()
			if v.Statement.SQL.Len() > 0 {
				var (
					vars = subdb.Statement.Vars

	})
	assertEqualSQL(t, `INSERT INTO "users" ("created_at","updated_at","deleted_at","name","age","birthday","company_id","manager_id","active") VALUES ('2021-10-18 00:00:00','2021-10-18 00:00:00',NULL,'foo',20,NULL,NULL,NULL,false) RETURNING "id"`, sql)

	// save
	user = &User{Name: "foo", Age: 20}
	user.CreatedAt = date
	user.UpdatedAt = date
	sql = DB.ToSQL(func(tx *gorm.DB) *gorm.DB {

import (
	"testing"
	"time"

	"gorm.io/gorm"
)

func TestDefaultValue(t *testing.T) {
	type Harumph struct {
		gorm.Model
		Email   string    `gorm:"not null;index:,unique"`
		Name    string    `gorm:"notNull;default:foo"`
		Name2   string    `gorm:"size:233;not null;default:'foo'"`
		Name3   string    `gorm:"size:233;notNull;default:''"`
		Age     int       `gorm:"default:18"`
		Created time.Time `gorm:"default:2000-01-02"`

	}

	type QueryResetNullValue struct {
		ID      int
		Name    string     `gorm:"default:NULL"`
		Flag    bool       `gorm:"default:NULL"`
		Number1 int64      `gorm:"default:NULL"`
		Number2 uint64     `gorm:"default:NULL"`
		Number3 float64    `gorm:"default:NULL"`
		Now     *time.Time `gorm:"defalut:NULL"`
		Item1Id string
		Item1   *QueryResetItem `gorm:"references:ID"`
		Item2Id string