UPDATE ... WHERE CURRENT OF

Syntax

UPDATE table-specification
   SET
       column = { variable | sql-expression }      
       [,...] 
   WHERE CURRENT OF cid

1. table-specification identifies the target table (see UPDATE for more details).
2. column is a name of a table column.
3. variable is a program variable, a record member or an array member used as a parameter buffer to provide values.
4. sql-expression is an expression supported by the database server, this can be a literal or NULL for example.
5. cid is the identifier of the database cursor declared for update.

Usage

Use UPDATE ... WHERE CURRENT OF to modify the values of the row currently pointed by the associated FOR UPDATE cursor.

The UPDATE statement does not advance the cursor to the next row, so the current row position remains unchanged.

The scope of reference of the cid cursor identifier is local to the module where it is declared. Therefore, you must execute the DECLARE,UPDATE or DELETE instructions in the same module.

There must be a current row in the result set. Make sure that the SQL status returned by the last FETCH is equal to zero.

If the DECLARE statement that created the cursor specified one or more columns in the FOR UPDATE clause, you are restricted to updating only those columns in a subsequent UPDATE ... WHERE CURRENT OF statement.