Deleting Rows

The DELETE statement removes any row or combination of rows from a table. You cannot recover a deleted row after the transaction is committed. (Transactions are discussed under Interrupted Modifications. For now, think of a transaction and a statement as the same thing.) If you want to delete rows from a table named from, you must first set the DELIMIDENT environment variable.

When you delete a row, you must also be careful to delete any rows of other tables whose values depend on the deleted row. If your database enforces referential constraints, you can use the ON DELETE CASCADE option of the CREATE TABLE or ALTER TABLE statements to allow deletes to cascade from one table in a relationship to another. For more information on referential constraints and the ON DELETE CASCADE option, refer to Referential Integrity.