# 2827 Referencing a Different Database In a UNION/EXCEPT/INTERSECT Query Causes Dangling Read Lock

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Whenever I execute a query like the following in the memory database context, a read lock is placed on the disk database catalog that doesn't get released when I close & free the query or when I drop the memory table. It gets released only when I close the session. Don't know if this is intentional, but when 2 or 3 of these locks are present, database.Open begins to fail and I'm getting these "cannot lock the catalog diskdb for read access" errors logged.