Updating or Deleting Rows Identified by Cursor Name
Specify a cursor name in the FOREACH statement if you intend to use the WHERE CURRENT OF cursor clause in UPDATE or DELETE statements that operate on the current row of cursor within the FOREACH loop. Although you cannot include the FOR UPDATE keywords in the SELECT ... INTO segment of the FOREACH statement, the cursor behaves like a FOR UPDATE cursor.
For a discussion of locking, see the section on Locking with an Update Cursor. For a discussion of isolation levels, see the description of SET ISOLATION statement.