Using UNION in a custom query

[eluser]Richard Testani[/eluser]
I've got a script that builds a query dynamically - but I'm having an issue with a UINION ALL.
I've looked on the boards and most call for either a completed query passed as an argument
or using the db-where method.

Using this method, the WHERE clause gets inserted into the query resulting in an error.
How can I either get rid of the WHERE string or is there some other dynamic method for using a UINION?

Thanks
Rich