To delete a selected row, the WHERE clause must be specified in the DELETE statement.

To delete all rows from a table, the following SQL must be executed:

• DELETE statement with the WHERE clause not specified
• PURGE TABLE statement

Points to be considered

• When all rows are to be deleted from a table that contains many rows, the PURGE TABLE statement deletes rows faster than the DELETE statement.
• When many rows are to be deleted with the DELETE statement, the lock mode should be set by first executing the LOCK statement with EXCLUSIVE specified in order to reduce the overhead for exclusive control.
• Deleting many rows with the DELETE statement has no effect on the free space in the user RDAREAs, because the segments remain allocated. To create free space, the PURGE TABLE statement must be used.