Method Replace

association.go:75–197

(values ...interface{})

}

func (association *Association) Replace(values ...interface{}) error {
	values = expandValues(values)

	if association.Error == nil {
		reflectValue := association.DB.Statement.ReflectValue
		rel := association.Relationship

		var oldBelongsToExpr clause.Expression
		// we have to record the old BelongsTo value
		if association.Unscope && rel.Type == schema.BelongsTo {
			var foreignFields []*schema.Field
			for _, ref := range rel.References {
				if !ref.OwnPrimaryKey {
					foreignFields = append(foreignFields, ref.ForeignKey)
				}
			}
			if _, fvs := schema.GetIdentityFieldValuesMap(association.DB.Statement.Context, reflectValue, foreignFields); len(fvs) > 0 {
				column, values := schema.ToQueryValues(rel.FieldSchema.Table, rel.FieldSchema.PrimaryFieldDBNames, fvs)
				oldBelongsToExpr = clause.IN{Column: column, Values: values}
			}
		}

		// save associations
		if association.saveAssociation( /*clear*/ true, values...); association.Error != nil {
			return association.Error
		}

		// set old association's foreign key to null
		switch rel.Type {
		case schema.BelongsTo:
			if len(values) == 0 {
				updateMap := map[string]interface{}{}
				switch reflectValue.Kind() {
				case reflect.Slice, reflect.Array:
					for i := 0; i < reflectValue.Len(); i++ {
						association.Error = rel.Field.Set(association.DB.Statement.Context, reflectValue.Index(i), reflect.Zero(rel.Field.FieldType).Interface())
					}
				case reflect.Struct:
					association.Error = rel.Field.Set(association.DB.Statement.Context, reflectValue, reflect.Zero(rel.Field.FieldType).Interface())
				}

				for _, ref := range rel.References {
					updateMap[ref.ForeignKey.DBName] = nil
				}

				association.Error = association.DB.UpdateColumns(updateMap).Error
			}
			if association.Unscope && oldBelongsToExpr != nil {
				association.Error = association.DB.Model(nil).Where(oldBelongsToExpr).Delete(reflect.New(rel.FieldSchema.ModelType).Interface()).Error
			}
		case schema.HasOne, schema.HasMany:
			var (
				primaryFields []*schema.Field
				foreignKeys   []string
				updateMap     = map[string]interface{}{}
				relValues     = schema.GetRelationsValues(association.DB.Statement.Context, reflectValue, []*schema.Relationship{rel})
				modelValue    = reflect.New(rel.FieldSchema.ModelType).Interface()
				tx            = association.DB.Model(modelValue)