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DELETE(5)
NAME
  DELETE - delete rows of a table

SYNOPSIS
  DELETE FROM [ ONLY ] table [ WHERE condition ]

  INPUTS

  table
       The name of an existing table.

  condition
       This is an SQL selection query which returns the rows which are to be
       deleted.

       Refer to the SELECT statement for further description of the WHERE
       clause.

  OUTPUTS

  DELETE count
       Message returned if items are successfully deleted. The count is the
       number of rows deleted.

       If count is 0, no rows were deleted.

DESCRIPTION
  DELETE removes rows which satisfy the WHERE clause from the specified
  table.

  If the condition (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(5)] is a PostgreSQL extension which provides a
       faster mechanism to remove all rows from a table.

  By default DELETE will delete tuples in the table specified and all its
  sub-tables. If you wish to only update the specific table mentioned, you
  should use the ONLY clause.

  You must have write access to the table in order to modify it, as well as
  read access to any table whose values are read in the condition.

USAGE
  Remove all films but musicals:

  DELETE FROM films WHERE kind <> 'Musical';
  SELECT * FROM films;

   code	 |	     title	     | did | date_prod	|  kind	  | len
  -------+---------------------------+-----+------------+---------+-------
   UA501 | West Side Story	     | 105 | 1961-01-03 | Musical | 02:32
   TC901 | The King and I	     | 109 | 1956-08-11 | Musical | 02:13
   WD101 | Bed Knobs and Broomsticks | 111 |		| Musical | 01:57
  (3 rows)

  Clear the table films:

  DELETE FROM films;
  SELECT * FROM films;

   code | title | did | date_prod | kind | len
  ------+-------+-----+-----------+------+-----
  (0 rows)

COMPATIBILITY
  SQL92

  SQL92 allows a positioned DELETE statement:

  DELETE FROM table WHERE
      CURRENT OF cursor

  where cursor identifies an open cursor.  Interactive cursors in PostgreSQL
  are read-only.

Index for Section 5

Alphabetical listing for D

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