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UPDATE(5)
NAME
  UPDATE - update rows of a table

SYNOPSIS
  UPDATE [ ONLY ] table SET column = { expression | DEFAULT } [, ...]
      [ FROM fromlist ]
      [ WHERE condition ]

DESCRIPTION
  UPDATE changes the values of the specified columns in all rows that satisfy
  the condition. Only the columns to be modified need be mentioned in the
  statement; columns not explicitly SET retain their previous values.

  By default, UPDATE will update rows in the specified table and all its
  subtables. If you wish to only update the specific table mentioned, you
  must use the ONLY clause.

  You must have the UPDATE privilege on the table to update it, as well as
  the SELECT privilege to any table whose values are read in the expressions
  or condition.

PARAMETERS
  table
       The name (optionally schema-qualified) of the table to update.

  column
       The name of a column in table.

  expression
       An expression to assign to the column. The expression may use the old
       values of this and other columns in the table.

  DEFAULT
       Set the column to its default value (which will be NULL if no specific
       default expression has been assigned to it).

  fromlist
       A list of table expressions, allowing columns from other tables to
       appear in the WHERE condition and the update expressions.

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

OUTPUTS
  On successful completion, an UPDATE command returns a command tag of the
  form

  UPDATE count

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

EXAMPLES
  Change the word Drama to Dramatic in the column kind of the table films:

  UPDATE films SET kind = 'Dramatic' WHERE kind = 'Drama';

  Adjust temperature entries and reset precipitation to its default value in
  one row of the table weather:

  UPDATE weather SET temp_lo = temp_lo+1, temp_hi = temp_lo+15, prcp = DEFAULT
    WHERE city = 'San Francisco' AND date = '2003-07-03';

COMPATIBILITY
  This command conforms to the SQL standard. The FROM clause is a PostgreSQL
  extension.

Index for Section 5

Alphabetical listing for U

Top of page