Index for Section 5

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VALUES()
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 expressions 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 effectively
  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 specifying
  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 example 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 systems.)

  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)]

Index for Section 5

Alphabetical listing for V

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