Firebird 2.1 Language Reference Update

PSQL statements
Description: Fetches the next data row from a cursor's result set and stores the column values in PSQL variables.
Syntax:
Notes:
FETCH cursorname INTO [:]varname [, [:]varname ...];
• The ROW_COUNT context variable will be 1 if the fetch returned a data row and 0 if the end of the set has
been reached.
• You can do a positioned UPDATE or DELETE on the fetched row with the WHERE CURRENT OF clause.
Example: See DECLARE ... CURSOR.
Available in: PSQL
Added in: 1.5
FOR EXECUTE STATEMENT ... DO
Description: See EXECUTE STATEMENT :: Any number of data rows returned.
Available in: PSQL
FOR SELECT ... INTO ... DO
Description: Executes a SELECT statement and retrieves the result set. In each iteration of the loop, the field
values of the current row are copied into local variables. Adding an AS CURSOR clause enables positioned
deletes and updates. FOR SELECT statements may be nested.
Syntax:
FOR
INTO [, ...]
[AS CURSOR name]
DO
::= A valid SELECT statement.
::= A PSQL variable name, optionally preceded by “:”
::= A single statement or a block of PSQL code.
• The SELECT statement may contain named SQL parameters, like in “select name || :sfx
from names where number = :num”. Each parameter must be a PSQL variable that has been
declared previously (this includes any in/out params of the PSQL module).
• Caution! If the value of a PSQL variable that is used in the SELECT statement changes during
execution of the loop, the statement may (but will not always) be re-evaluated for the remaining
rows. In general, this situation should be avoided. If you really need this behaviour, test your code
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