Method AlterColumn

migrator/migrator.go:412–426

AlterColumn alter value's `field` column's type based on schema definition

(value interface{}, field string)

// AlterColumn alter value's `field` column's type based on schema definition
func (m Migrator) AlterColumn(value interface{}, field string) error {
	return m.RunWithValue(value, func(stmt *gorm.Statement) error {
		if stmt.Schema != nil {
			if field := stmt.Schema.LookUpField(field); field != nil {
				fieldType := m.FullDataTypeOf(field)
				return m.DB.Exec(
					"ALTER TABLE ? ALTER COLUMN ? TYPE ?",
					m.CurrentTable(stmt), clause.Column{Name: field.DBName}, fieldType,
				).Error

			}
		}
		return fmt.Errorf("failed to look up field with name: %s", field)
	})
}

// HasColumn check has column `field` for value or not
func (m Migrator) HasColumn(value interface{}, field string) bool {