values(5)

NAME

       VALUES - compute a set of rows

SYNOPSIS

       VALUES ( expression [, ...] ) [, ...]
           [ ORDER BY sort_expression [ ASC | DESC | USING operator ] [, ...] ]
           [ LIMIT { count | ALL } ]
           [ OFFSET start ]

DESCRIPTION

       VALUES  computes  a  row  value or set of row values specified by value
       expressions. It is most commonly used to generate a ``constant  table''
       within a larger command, but it can be used on its own.

       When  more  than  one row is specified, all the rows must have the same
       number of elements. The data types of the resulting table's columns are
       determined  by  combining the explicit or inferred types of the expres-
       sions appearing in that column, using the same rules as for UNION  (see
       in the documentation).

       Within  larger  commands, VALUES is syntactically allowed anywhere that
       SELECT is. Because it is treated like a SELECT by the  grammar,  it  is
       possible  to  use the ORDER BY, LIMIT, and OFFSET clauses with a VALUES
       command.

PARAMETERS

       expression
              A constant or expression to compute and insert at the  indicated
              place  in  the  resulting  table (set of rows). In a VALUES list
              appearing at the top level of an INSERT, an  expression  can  be
              replaced  by  DEFAULT  to indicate that the destination column's
              default value should be inserted. DEFAULT cannot  be  used  when
              VALUES appears in other contexts.

       sort_expression
              An  expression  or  integer  constant indicating how to sort the
              result rows. This expression may refer to  the  columns  of  the
              VALUES  result  as  column1,  column2, etc. For more details see
              ORDER BY Clause [select(5)].

       operator
              A sorting operator. For details see ORDER BY Clause [select(5)].

       count  The maximum number of rows to  return.  For  details  see  LIMIT
              Clause [select(5)].

       start  The  number of rows to skip before starting to return rows.  For
              details see LIMIT Clause [select(5)].

NOTES

       VALUES lists with very large numbers of rows should be avoided, as  you
       may  encounter  out-of-memory  failures  or  poor  performance.  VALUES
       appearing within INSERT is a special case (because the  desired  column
       types  are  known  from  the  INSERT's  target  table,  and need not be
       inferred by scanning the VALUES list), so it can  handle  larger  lists
       than are practical in other contexts.

EXAMPLES

       A bare VALUES command:

       VALUES (1, 'one'), (2, 'two'), (3, 'three');

       This  will  return  a  table of two columns and three rows. It's effec-
       tively equivalent to

       SELECT 1 AS column1, 'one' AS column2
       UNION ALL
       SELECT 2, 'two'
       UNION ALL
       SELECT 3, 'three';

       More usually, VALUES is used within a larger  SQL  command.   The  most
       common use is in INSERT:

       INSERT INTO films (code, title, did, date_prod, kind)
           VALUES ('T_601', 'Yojimbo', 106, '1961-06-16', 'Drama');

       In  the  context  of INSERT, entries of a VALUES list can be DEFAULT to
       indicate that the column default should be used here instead of  speci-
       fying a value:

       INSERT INTO films VALUES
           ('UA502', 'Bananas', 105, DEFAULT, 'Comedy', '82 minutes'),
           ('T_601', 'Yojimbo', 106, DEFAULT, 'Drama', DEFAULT);

       VALUES  can also be used where a sub-SELECT might be written, for exam-
       ple in a FROM clause:

       SELECT f.*
         FROM films f, (VALUES('MGM', 'Horror'), ('UA', 'Sci-Fi')) AS t (studio, kind)
         WHERE f.studio = t.studio AND f.kind = t.kind;

       UPDATE employees SET salary = salary * v.increase
         FROM (VALUES(1, 200000, 1.2), (2, 400000, 1.4)) AS v (depno, target, increase)
         WHERE employees.depno = v.depno AND employees.sales >= v.target;

       Note that an AS clause is required  when  VALUES  is  used  in  a  FROM
       clause,  just  as  is  true  for SELECT. It is not required that the AS
       clause specify names for all the columns, but it's good practice to  do
       so.   (The default column names for VALUES are column1, column2, etc in
       PostgreSQL, but these names might be different in other  database  sys-
       tems.)

       When VALUES is used in INSERT, the values are all automatically coerced
       to the data type of the corresponding  destination  column.  When  it's
       used in other contexts, it may be necessary to specify the correct data
       type. If the entries are all quoted  literal  constants,  coercing  the
       first is sufficient to determine the assumed type for all:

       SELECT * FROM machines
       WHERE ip_address IN (VALUES('192.168.0.1'::inet), ('192.168.0.10'), ('192.168.1.43'));

              Tip:  For  simple  IN tests, it's better to rely on the list-of-
              scalars form of IN than to write a VALUES query as shown  above.
              The  list  of  scalars method requires less writing and is often
              more efficient.

COMPATIBILITY

       VALUES conforms to the SQL standard, except that LIMIT and  OFFSET  are
       PostgreSQL extensions.

SEE ALSO

       INSERT [insert(5)], SELECT [select(l)]

SQL - Language Statements         2008-06-08                          VALUES()