Example: UPDATE With a Subquery in its WHERE Clause - Advanced SQL Engine - Teradata Database

The following examples perform the same UPDATE operation using either a subquery join with a derived table or a simple equality join on column_1 in table_1 and table_2.

     UPDATE table_1
     SET column_1 = 1
     WHERE column_1 IN (SELECT column_2
                        FROM table_2);

     UPDATE table_1
     SET column_1 = 1
     WHERE table_1.column_1=table_2.column_1;