• It looks like you are trying to run through sys.tables or whatever and do something to each table encountered, although as Gail points out, it's bl00dy hard to tell from your description! If you are, then why not use a cursor (fast-forward read-only, of course).

    “Write the query the simplest way. If through testing it becomes clear that the performance is inadequate, consider alternative query forms.” - Gail Shaw

    For fast, accurate and documented assistance in answering your questions, please read this article.
    Understanding and using APPLY, (I) and (II) Paul White
    Hidden RBAR: Triangular Joins / The "Numbers" or "Tally" Table: What it is and how it replaces a loop Jeff Moden