Building WHERE SQL clauses

Hello all. I'm using PHP to build a query for a database that consists of multiple tables, all with identical attribues. A typical syntax try looks like this: SELECT * FROM chico, harpo WHERE operator = "Bill" OR operator = "Jessica" MySQL responds with this: Couldn't execute query.Column 'operator' in where clause is ambiguous I was hoping that since the tables are identical all I would need to do is list the attribute values not have to append them to the table names. Is there any way to do this? Perhaps with a setting in MySQL or a different syntax (JOIN, UNION, ...)? If not are there available some canned code snippets that build these types of strings from values passed in the $_POST array. Thanks for any insights on this. --- Mike