Method MigrateColumnUnique

migrator/migrator.go:599–617

(value interface{}, field *schema.Field, columnType gorm.ColumnType)

}

func (m Migrator) MigrateColumnUnique(value interface{}, field *schema.Field, columnType gorm.ColumnType) error {
	unique, ok := columnType.Unique()
	if !ok || field.PrimaryKey {
		return nil // skip primary key
	}
	// By default, ColumnType's Unique is not affected by UniqueIndex, so we don't care about UniqueIndex.
	return m.RunWithValue(value, func(stmt *gorm.Statement) error {
		// We're currently only receiving boolean values on `Unique` tag,
		// so the UniqueConstraint name is fixed
		constraint := m.DB.NamingStrategy.UniqueName(stmt.Table, field.DBName)
		if unique && !field.Unique {
			return m.DB.Migrator().DropConstraint(value, constraint)
		}
		if !unique && field.Unique {
			return m.DB.Migrator().CreateConstraint(value, constraint)
		}
		return nil
	})
}

// ColumnTypes return columnTypes []gorm.ColumnType and execErr error
func (m Migrator) ColumnTypes(value interface{}) ([]gorm.ColumnType, error) {