>>-UPDATE------------------------------------------------------->
 
                                                                                        (4)
>--+-+---------------------------------------------+--| Table Options |--| SET Clause |-------| Where Options |-+-><
   | |  (1)    (2)                            (3)  |                                                            |
   | '---------------| Optimizer Directives |------'                                                            |
   |                              (5)                  (4)                                                      |
   '-| Collection-Derived Table |-------| SET Clause |-------+-----------------------------------------+--------'
                                                             |  (6)    (7)                             |
                                                             '---------------WHERE CURRENT OFcursor_id-'
 
Table Options:
 
|--+-table-----------------------------+------------------------|
   +-view------------------------------+
   +-synonym---------------------------+
   |  (1)    (2)                       |
   '---------------ONLY--+-(table )--+-'
                         '-(synonym)-'
 
Where Options:
 
|--+-+--------------------------------+--+---------------------------+-+--|
   | |                           (8)  |  |                      (9)  | |
   | '-| Subset of FROM Clause |------'  '-WHERE--| Condition |------' |
   |  (6)    (7)                                                       |
   '---------------WHERE CURRENT OFcursor_id---------------------------'
 

1. Informix extension
2. Dynamic Server only
3. See page Optimizer Directives
4. See page SET Clause
5. See page Collection-Derived Table
6. ESQL/C only
7. Stored Procedure Language only
8. See page Subset of FROM Clause
9. See page Condition

Use the UPDATE statement to update any of the following types of objects:

• A row in a table: a single row, a group of rows, or all rows in a table
• For Dynamic Server, an element in a collection variable
• An ESQL/C row variable: a field or all fields

For information on how to update elements of a collection variable, see Collection-Derived Table. Sections that follow in this description of the UPDATE statement describe how to update a row in a table.

You must either own the table or have the Update privilege for the table; see GRANT. To update data in a view, you must have the Update privilege, and the view must meet the requirements that are explained in Updating Rows Through a View.

The cursor (as defined in the SELECT ... FOR UPDATE portion of a DECLARE statement) can contain only column names. If you omit the WHERE clause, all rows of the target table are updated.

If you are using effective checking and the checking mode is set to IMMEDIATE, all specified constraints are checked at the end of each UPDATE statement. If the checking mode is set to DEFERRED, all specified constraints are not checked until the transaction is committed.

In Extended Parallel Server, if UPDATE is constructed in such a way that a single row might be updated more than once, the database server returns an error. If the new value is the same in every update, however, the database server allows the update to take place without reporting an error.

In DB-Access, if you omit the WHERE clause and are in interactive mode, DB–Access does not run the UPDATE statement until you confirm that you want to change all rows. If the statement is in a command file, however, and you are running at the command line, the statement executes immediately.