I'm guessing ora_dict_obj_type is a column in dherri.schema? If so, you are using row-level data in a statement-level trigger. You need to add the magic words that turn the trigger into a row level trigger. It's "for each row" or words to that effect. You'll find the exact syntax in the manual. Here's the trigger's text: CREATE OR REPLACE TRIGGER sys.cp_tab_before_drop_btg BEFORE drop ON dherri.SCHEMA WHEN ( ora_dict_obj_type = 'TABLE' AND ( ora_dict_obj_name LIKE 'SCORE\_ACCT\_TB\_%' ESCAPE '\' ) )