DELETE — delete rows of a table
[ WITH [ RECURSIVE ]with_query[, ...] ]DELETE FROM [ ONLY ]table_name[ * ] [ [ AS ]alias][ USINGusing_list][ WHEREcondition| WHERE CURRENT OFcursor_name][ RETURNING * |output_expression[ [ AS ]output_name] [, ...] ]
DELETEdeletes rows that satisfy the
WHEREclause from the specified table. If the
WHEREclause is absent, the effect is to delete all rows in the table. The result is a valid, but empty table.
TRUNCATEprovides a faster mechanism to remove all rows from a table.
There are two ways to delete rows in a table using information contained in other tables in the database: using sub-selects, or specifying additional tables in the
USINGclause. Which technique is more appropriate depends on the specific circumstances.
DELETEto compute and return value(s) based on each row actually deleted. Any expression using the table's columns, and/or columns of other tables mentioned in
USING, can be computed. The syntax of the
RETURNINGlist is identical to that of the output list of
You must have the
DELETEprivilege on the table to delete from it, as well as the
SELECTprivilege for any table in the
USINGclause or whose values are read in the
The name (optionally schema-qualified) of the table to delete rows from. If
ONLYis specified before the table name, matching rows are deleted from the named table only. If
ONLYis not specified, matching rows are also deleted from any tables inheriting from the named table. Optionally,
*can be specified after the table name to explicitly indicate that descendant tables are included.
A substitute name for the target table. When an alias is provided, it completely hides the actual name of the table. For example, given
DELETE FROM foo AS f, the remainder of the
DELETEstatement must refer to this table as
A list of table expressions, allowing columns from other tables to appear in the
WHEREcondition. This is similar to the list of tables that can be specified in the
SELECTstatement; for example, an alias for the table name can be specified. Do not repeat the target table in the
using_list, unless you wish to set up a self-join.
An expression that returns a value of type
boolean. Only rows for which this expression returns
truewill be deleted.
The name of the cursor to use in a
WHERE CURRENT OFcondition. The row to be deleted is the one most recently fetched from this cursor. The cursor must be a non-grouping query on the
DELETE's target table. Note that
WHERE CURRENT OFcannot be specified together with a Boolean condition. SeeDECLAREfor more information about using cursors with
WHERE CURRENT OF.
An expression to be computed and returned by the
DELETEcommand after each row is deleted. The expression can use any column names of the table named by_
table_name_or table(s) listed in
*to return all columns.
A name to use for a returned column.
On successful completion, a
DELETEcommand returns a command tag of the form
count_is the number of rows deleted. Note that the number may be less than the number of rows that matched the
conditionwhen deletes were suppressed by a
BEFORE DELETEtrigger. If
count_is 0, no rows were deleted by the query (this is not considered an error).
DELETEcommand contains a
RETURNINGclause, the result will be similar to that of a
SELECTstatement containing the columns and values defined in the
RETURNINGlist, computed over the row(s) deleted by the command.
PostgreSQLlets you reference columns of other tables in the
WHEREcondition by specifying the other tables in the
USINGclause. For example, to delete all films produced by a given producer, one can do:
DELETE FROM films USING producersWHERE producer_id = producers.id AND producers.name = 'foo';
What is essentially happening here is a join between
producers, with all successfully joined
filmsrows being marked for deletion. This syntax is not standard. A more standard way to do it is:
DELETE FROM filmsWHERE 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
DELETE FROM films;
Delete completed tasks, returning full details of the deleted rows:
DELETE FROM tasks WHERE status = 'DONE' RETURNING *;
Delete the row of
taskson which the cursor
c_tasksis currently positioned:
DELETE FROM tasks WHERE CURRENT OF c_tasks;
This command conforms to theSQLstandard, except that the
RETURNINGclauses arePostgreSQLextensions, as is the ability to use