DELETE Statement

The DELETE statement removes entire rows of data from a specified table or view. For a full description of the DELETE statement, see Oracle Database SQL Reference.

Syntax

Description of delete_statement.gif follows

Description of the illustration delete_statement.gif

Keyword and Parameter Description

alias

Another (usually short) name for the referenced table or view. Typically referred to later in the WHERE clause.

BULK COLLECT

Returns columns from the deleted rows into PL/SQL collections, as specified by the RETURNING INTO list. The corresponding columns must store scalar (not composite) values. For more information, see "Reducing Loop Overhead for DML Statements and Queries (FORALL, BULK COLLECT)".

returning_clause

Returns values from the deleted rows, eliminating the need to SELECT the rows first. You can retrieve the column values into individual variables or into collections. You cannot use the RETURNING clause for remote or parallel deletes. If the statement does not affect any rows, the values of the variables specified in the RETURNING clause are undefined.

subquery

A SELECT statement that provides a set of rows for processing. Its syntax is like the select_into_statement without the INTO clause. See "SELECT INTO Statement".

table_reference

A table or view, which must be accessible when you execute the DELETE statement, and for which you must have DELETE privileges.

TABLE (subquery2)

The operand of TABLE is a SELECT statement that returns a single column value, which must be a nested table. Operator TABLE informs Oracle that the value is a collection, not a scalar value.

WHERE CURRENT OF cursor_name

Refers to the latest row processed by the FETCH statement associated with the cursor identified by cursor_name. The cursor must be FOR UPDATE and must be open and positioned on a row. If the cursor is not open, the CURRENT OF clause causes an error.

If the cursor is open, but no rows have been fetched or the last fetch returned no rows, PL/SQL raises the predefined exception NO_DATA_FOUND.

WHERE search_condition

Conditionally chooses rows to be deleted from the referenced table or view. Only rows that meet the search condition are deleted. If you omit the WHERE clause, all rows in the table or view are deleted.

Usage Notes

You can use the DELETE WHERE CURRENT OF statement after a fetch from an open cursor (this includes implicit fetches executed in a cursor FOR loop), provided the associated query is FOR UPDATE. This statement deletes the current row; that is, the one just fetched.

The implicit cursor SQL and the cursor attributes %NOTFOUND, %FOUND, and %ROWCOUNT let you access useful information about the execution of a DELETE statement.

Examples

The following statement deletes the rows that match a condition:

DELETE FROM bonus WHERE sales_amt < quota;

The following statement returns two column values from a deleted row into local variables:

DECLARE
   my_empno emp.empno%TYPE;
   my_ename emp.ename%TYPE;
   my_job   emp.job%TYPE;
BEGIN
   ...
   DELETE FROM emp WHERE empno = my_empno
      RETURNING ename, job INTO my_ename, my_job;
END;

You can combine the BULK COLLECT clause with a FORALL statement, in which case, the SQL engine bulk-binds column values incrementally. In the following example, if collection depts has 3 elements, each of which causes 5 rows to be deleted, then collection enums has 15 elements when the statement completes:

FORALL j IN depts.FIRST..depts.LAST
   DELETE FROM emp WHERE deptno = depts(j)
      RETURNING empno BULK COLLECT INTO enums;

The column values returned by each execution are added to the values returned previously.