FOR statement

Description

Repeats the execution of a statement list once for each row in a cursor.

Syntax

[ statement-label: ]
... FOR for-loop-name AS cursor-name
... CURSOR FOR statement
... [ { FOR UPDATE | FOR READ ONLY } ]
... DO statement-list
... END FOR [ statement-label ]

Examples

Example 1

The following fragment illustrates the use of the FOR loop:

FOR names AS curs CURSOR FOR
SELECT emp_lname
FROM employee
DO
	CALL search_for_name( emp_lname );
END FOR;

Usage

FOR is a control statement that lets you execute a list of SQL statements once for each row in a cursor. The FOR statement is equivalent to a compound statement with a DECLARE for the cursor and a DECLARE of a variable for each column in the result set of the cursor followed by a loop that fetches one row from the cursor into the local variables and executes statement-list once for each row in the cursor.

The name and data type of the local variables that are declared are derived from the statement used in the cursor. With a SELECT statement, the data type is the data type of the expressions in the select list. The names are the select list item aliases where they exist; otherwise, they are the names of the columns. Any select list item that is not a simple column reference must have an alias. With a CALL statement, the names and data types are taken from the RESULT clause in the procedure definition.

The LEAVE statement can be used to resume execution at the first statement after the END FOR. If the ending statement-label is specified, it must match the beginning statement-label.

None.

Standards

Permissions

None

See also