DELETE (SQL)

This document covers the following topics:

Belongs to Function Group: Database Access and Update

DELETE (SQL) Usage

The SQL DELETE statement is used to delete either rows in a table without using a cursor ("searched" DELETE) or rows in a table to which a cursor is positioned ("positioned" DELETE).

Two different structures are possible.

Syntax 1 - Searched DELETE

The "searched" DELETE statement is a stand-alone statement not related to any SELECT statement. With a single statement you can delete zero, one, multiple or all rows of a table. The rows to be deleted are determined by a search-condition that is applied to the table. Optionally, the table name can be assigned a correlation-name.

Note
The number of rows that have actually been deleted with a "searched" DELETE can be ascertained by using the system variable *ROWCOUNT; see System Variables documentation.

Common Set Syntax:

DELETE FROM table-name [correlation-name] [WHERE search-condition]

Extended Set Syntax:

DELETE FROM table-name [correlation-name]
[WHERE search-condition]

WITH

RR
RS
CS

[QUERYNO integer]

For an explanation of the symbols used in the syntax diagram, see Syntax Symbols.

Syntax Element Description:

Syntax Element Description
FROM table-name
FROM Clause:

Specifies the table from which the rows are to be deleted.
correlation-name
Correlation Name:

Optional. The table name can be assigned a correlation-name.

WHERE search-condition
WHERE Clause:

Specifies the selection criteria for the rows to be deleted.

If no WHERE clause is specified, the entire table is deleted.

WITH
WITH Isolation Level Clause:

Enables the explicit specification of the isolation level used when locating the row to be deleted.

This clause belongs to the SQL Extended Set.

It is only valid against Db2 databases. When used against other databases, it will cause runtime errors.

CS Cursor Stability
RR Repeatable Read
RS Read Stability
QUERYNO integer
QUERYNO Clause:

This clause belongs to the SQL Extended Set.

This clause is not currently supported and will be ignored.

Syntax 2 - Positioned DELETE

The "positioned" DELETE statement always refers to a cursor within a database loop. Therefore the table referenced by a positioned DELETE statement must be the same as the one referenced by the corresponding SELECT statement, otherwise an error message is returned. A positioned DELETE cannot be used with a non-cursor selection.

The functionality of the positioned DELETE statement corresponds to that of the "native" Natural DELETE statement.

DELETE FROM table-name WHERE CURRENT OF CURSOR [(r)]

For an explanation of the symbols used in the syntax diagram, see Syntax Symbols.

Syntax Element Description:

Syntax Element Description
FROM table-name WHERE CURRENT OF CURSOR
FROM Clause:

This clause specifies the table from which the rows are to be deleted.
(r)
Statement Reference:

The (r) notation is used to reference the statement which was used to select the row to be deleted. If no statement reference is specified, the DELETE statement is related to the innermost active processing loop in which a database record was selected.

FOR ROW ... OF ROWSET
FOR ROW … OF ROWSET Clause:

This clause belongs to the SQL Extended Set.

The optional FOR ROW ... OF ROWSET clause for positioned SQL DELETE statements specifies which row of the current rowset has to be deleted. It should only be specified if the DELETE statement is related to a SELECT statement which uses rowset positioning and which has column arrays in its INTO clause, see into-clause. If this clause is omitted, all rows of the current rowset are deleted.

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