This document covers the following topics:
Belongs to Function Group: Database Access and Update
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.
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
|
For explanations of the symbols used in the syntax diagram, see Syntax Symbols.
Syntax Element Description:
Syntax Element | Description | |
---|---|---|
FROM
table-name
|
FROM Clause:
This 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:
This clause is used to specify the selection criteria for the rows to be deleted. If no |
|
WITH
|
WITH Isolation Level Clause:
This clause belongs to the SQL Extended Set. This clause enables the explicit specification of the isolation level used when locating the row to be deleted. 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 |
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 explanations of the symbols used in the syntax diagram, see Syntax Symbols.
Syntax Element Description: