return nil
	}

	if hasPolymorphicRelation(field.TagSettings) {
		schema.buildPolymorphicRelation(relation, field)
	} else if many2many := field.TagSettings["MANY2MANY"]; many2many != "" {
		schema.buildMany2ManyRelation(relation, field, many2many)
	} else if belongsTo := field.TagSettings["BELONGSTO"]; belongsTo != "" {
		schema.guessRelation(relation, field, guessBelongs)
	} else {

		t.Fatalf("Should find 3 tags")
	}

	var blog1 Blog
	DB.Preload("Tags").Find(&blog1)
	if !compareTags(blog1.Tags, []string{"tag1", "tag2", "tag3"}) {
		t.Fatalf("Preload many2many relations")
	}

	// Replace
	tag5 := &Tag{Locale: "ZH", Value: "tag5"}
	tag6 := &Tag{Locale: "ZH", Value: "tag6"}
	DB.Model(&blog).Association("Tags").Replace(tag5, tag6)
	var tags2 []Tag

				} else {
					db.AddError(fmt.Errorf("relation %s not found", association))
					return nil
				}
			}

			if q.limitPerRecord > 0 {
				if relation.JoinTable != nil {
					tx.AddError(fmt.Errorf("many2many relation %s don't support LimitPerRecord", association))
					return tx
				}

				refColumns := []clause.Column{}
				for _, rel := range relation.References {
					if rel.OwnPrimaryKey {

				} else {
					association.Error = tx.Where(clause.IN{Column: column, Values: values}).UpdateColumns(updateMap).Error
				}
			}
		case schema.Many2Many:
			var (
				primaryFields, relPrimaryFields     []*schema.Field
				joinPrimaryKeys, joinRelPrimaryKeys []string
				modelValue                          = reflect.New(rel.JoinTable.ModelType).Interface()

		return &uni, stmt.Table
	}

	getTable := func(rel *schema.Relationship) string {
		switch rel.Type {
		case schema.HasOne, schema.HasMany:
			return rel.FieldSchema.Table
		case schema.Many2Many:
			return rel.JoinTable.Table
		}
		return stmt.Table
	}

	for _, rel := range stmt.Schema.Relationships.Relations {
		if constraint := rel.ParseConstraint(); constraint != nil && constraint.Name == name {

		{"accounts", "fk_users_account"},
		{"users", "fk_users_team"},
		{"users", "fk_users_company"},
	} {
		if !DB.Migrator().HasConstraint(indexes[0], indexes[1]) {
			t.Fatalf("Failed to find index for many2many for %v %v", indexes[0], indexes[1])
		}
	}
}

func TestAutoMigrateInt8PGAndGaussDB(t *testing.T) {
	if DB.Dialector.Name() != "postgres" && DB.Dialector.Name() != "gaussdb" {
		return
	}