parseCheckConstraints = stmt.Schema.ParseCheckConstraints()
				)
				for _, dbName := range stmt.Schema.DBNames {
					var foundColumn gorm.ColumnType

					for _, columnType := range columnTypes {
						if columnType.Name() == dbName {
							foundColumn = columnType
							break
						}
					}

					if foundColumn == nil {
						// not found, add column

	NewValuePool           FieldNewValuePool

	// In some db (e.g. MySQL), Unique and UniqueIndex are indistinguishable.
	// When a column has a (not Mul) UniqueIndex, Migrator always reports its gorm.ColumnType is Unique.
	// It causes field unnecessarily migration.
	// Therefore, we need to record the UniqueIndex on this column (exclude Mul UniqueIndex) for MigrateColumnUnique.
	UniqueIndex string
}