Delete all rows of a table

The DELETE statement specifies a table and usually contains a WHERE clause that designates the row or rows that are to be removed from the table. If the WHERE clause is left out, all rows are deleted.

Important: Do not execute the following statement.

DELETE FROM customer;

You can write DELETE statements with or without the FROM keyword.

DELETE customer;

Because these DELETE statements do not contain a WHERE clause, all rows from the customer table are deleted. If you attempt an unconditional delete using the menu options, the program warns you and asks for confirmation. However, an unconditional DELETE from within a program can occur without warning.

If you want to delete rows from a table named from, you must first set the DELIMIDENT environment variable, or qualify the name of the table with the name of its owner:

DELETE legree.from;

For more information about delimited identifiers and DELIMIDENT environment variable, see the descriptions of the Quoted String expression and of the Identifier segment in the HCL OneDB™ Guide to SQL: Syntax.