Firebird 2.1 Language Reference Update

DML statements
Description: A DELETE statement removing at most one row may optionally include a RETURNING clause in
order to return values from the deleted row. The clause, if present, need not contain all of the relation's columns
and may also contain other columns or expressions.
Examples:
Notes:
delete from Scholars
where firstname = 'Henry' and lastname = 'Higgins'
returning lastname, fullname, id
delete from Dumbbells
order by iq desc
rows 1
returning lastname, iq into :lname, :iq;
• In DSQL, a statement with a RETURNING clause always returns exactly one row. If no record was actually
deleted, the fields in this row are all NULL. This behaviour may change in a later version of Firebird. In PSQL,
if no row was deleted, nothing is returned, and the receiving variables keep their existing values.
ROWS
Available in: DSQL, PSQL
Added in: 2.0
Description: Limits the amount of rows deleted to a specified number or range.
Syntax:
ROWS [TO ]
, ::= Any expression evaluating to an integer.
With a single argument m, the deletion is limited to the first m rows of the dataset defined by the table or view
and the optional WHERE and ORDER BY clauses.
Points to note:
• If m > the total number of rows in the dataset, the entire set is deleted.
• If m = 0, no rows are deleted.
• If m < 0, an error is raised.
With two arguments m and n, the deletion is limited to rows m to n inclusively. Row numbers are 1-based.
Points to note when using two arguments:
• If m > the total number of rows in the dataset, no rows are deleted.
• If m lies within the set but n doesn't, the rows from m to the end of the set are deleted.
• If m < 1 or n < 1, an error is raised.
• If n = m-1, no rows are deleted.
• If n < m-1, an error is raised.
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