Provided by: postgresql-client-9.1_9.1.1-1_i386 bug

NAME

       DELETE - delete rows of a table

SYNOPSIS

       [ WITH [ RECURSIVE ] with_query [, ...] ]
       DELETE FROM [ ONLY ] table [ [ AS ] alias ]
           [ USING using_list ]
           [ WHERE condition | WHERE CURRENT OF cursor_name ]
           [ RETURNING * | output_expression [ [ AS ] output_name ] [, ...] ]

DESCRIPTION

       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(7) is a PostgreSQL extension that provides 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
       mentioned, you must use the ONLY clause.

       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 USING clause. Which technique is
       more appropriate depends on the specific circumstances.

       The optional RETURNING clause causes DELETE to 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 RETURNING list is identical to that of
       the output list of SELECT.

       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.

PARAMETERS

       with_query
           The WITH clause allows you to specify one or more subqueries that
           can be referenced by name in the DELETE query. See Section 7.8,
           "WITH Queries (Common Table Expressions)", in the documentation and
           SELECT(7) for details.

       ONLY
           If specified, delete rows from the named table only. When not
           specified, any tables inheriting from the named table are also
           processed.

       table
           The name (optionally schema-qualified) of an existing table.

       alias
           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 DELETE statement
           must refer to this table as f not foo.

       using_list
           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 of a SELECT
           statement; 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.

       condition
           An expression that returns a value of type boolean. Only rows for
           which this expression returns true will be deleted.

       cursor_name
           The name of the cursor to use in a WHERE CURRENT OF condition. 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 OF cannot be specified
           together with a Boolean condition. See DECLARE(7) for more
           information about using cursors with WHERE CURRENT OF.

       output_expression
           An expression to be computed and returned by the DELETE command
           after each row is deleted. The expression can use any column names
           of the table or table(s) listed in USING. Write * to return all
           columns.

       output_name
           A name to use for a returned column.

OUTPUTS

       On successful completion, a DELETE command returns a command tag of the
       form

           DELETE count

       The count is the number of rows deleted. If count is 0, no rows matched
       the condition (this is not considered an error).

       If the DELETE command contains a RETURNING clause, the result will be
       similar to that of a SELECT statement containing the columns and values
       defined in the RETURNING list, computed over the row(s) deleted by the
       command.

NOTES

       PostgreSQL lets you reference columns of other tables in the WHERE
       condition by specifying the other tables in the USING clause. For
       example, to delete all films produced by a given producer, one can 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
       producers, 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.

EXAMPLES

       Delete all films but musicals:

           DELETE FROM films WHERE kind <> 'Musical';

       Clear the table films:

           DELETE FROM films;

       Delete completed tasks, returning full details of the deleted rows:

           DELETE FROM tasks WHERE status = 'DONE' RETURNING *;

       Delete the row of tasks on which the cursor c_tasks is currently
       positioned:

           DELETE FROM tasks WHERE CURRENT OF c_tasks;

COMPATIBILITY

       This command conforms to the SQL standard, except that the USING and
       RETURNING clauses are PostgreSQL extensions, as is the ability to use
       WITH with DELETE.