Informix allows positioned UPDATEs and DELETEs with the "WHERE CURRENT OF cursor" clause, if the cursor has been DECLARED with a SELECT ... FOR UPDATE statement.

Microsoft™ SQL Server

UPDATE/DELETE ... WHERE CURRENT OF is supported with Microsoft SQL Server by using server side cursors.


With Microsoft SQL Server, UPDATE/DELETE ... WHERE CURRENT OF instructions are executed as is without any SQL translation: Since BDL cursors for the SELECT FOR UPDATE statements are implemented with ODBC server cursors, native positioned update/delete can take place in SQL Server.

As a replacement of WHERE CURRENT OF, if the database table is defined with a primary key column, use the value fetched from the SELECT [FOR UPDATE] cursor in the WHERE clause of the UPDATE/DELETE statement.