DELETE() SQL Commands DELETE()NAME
DELETE - delete rows of a table
DELETE FROM [ ONLY ] table
[ USING usinglist ]
[ WHERE condition ]
DELETE deletes rows that satisfy the WHERE clause from the specified
table. If the WHERE clause is absent, the effect is to delete all rows
in the table. The result is a valid, but empty table.
Tip: TRUNCATE [truncate(7)] is a PostgreSQL extension that pro‐
vides a faster mechanism to remove all rows from a table.
By default, DELETE will delete rows in the specified table and all its
child tables. If you wish to delete only from the specific table men‐
tioned, you must use the ONLY clause.
There are two ways to delete rows in a table using information con‐
tained in other tables in the database: using sub-selects, or specify‐
ing additional tables in the USING clause. Which technique is more
appropriate depends on the specific circumstances.
You must have the DELETE privilege on the table to delete from it, as
well as the SELECT privilege for any table in the USING clause or whose
values are read in the condition.
ONLY If specified, delete rows from the named table only. When not
specified, any tables inheriting from the named table are also
table The name (optionally schema-qualified) of an existing table.
A list of table expressions, allowing columns from other tables
to appear in the WHERE condition. This is similar to the list of
tables that can be specified in the FROM Clause [select(7)] of a
SELECT statement; for example, an alias for the table name can
be specified. Do not repeat the target table in the usinglist,
unless you wish to set up a self-join.
An expression returning a value of type boolean, which deter‐
mines the rows that are to be deleted.
On successful completion, a DELETE command returns a command tag of the
The count is the number of rows deleted. If count is 0, no rows matched
the condition (this is not considered an error).
PostgreSQL lets you reference columns of other tables in the WHERE con‐
dition by specifying the other tables in the USING clause. For example,
to delete all films produced by a given producer, one might do
DELETE FROM films USING producers
WHERE producer_id = producers.id AND producers.name = 'foo';
What is essentially happening here is a join between films and produc‐
ers, with all successfully joined films rows being marked for deletion.
This syntax is not standard. A more standard way to do it is
DELETE FROM films
WHERE producer_id IN (SELECT id FROM producers WHERE name = 'foo');
In some cases the join style is easier to write or faster to execute
than the sub-select style.
Delete all films but musicals:
DELETE FROM films WHERE kind <> 'Musical';
Clear the table films:
DELETE FROM films;
This command conforms to the SQL standard, except that the USING clause
and the ability to reference other tables in the WHERE clause are Post‐
SQL - Language Statements 2005-11-05 DELETE()