Searching lists is something computer scientists have been working on for generations. Using a database tool is not always the quickest method. Visier, as Brian has stated, is designed for such searches and is probably your weapon of choice. I build specialized search engines for specific tasks, such as matching stars in a given field with previous observations, and you can usually optimize such searches far better than with a general tool. For a very quick example, just order the big list in RA and index into the list for each candidate; you then only have a very small part of the big catalog that has to be searched. Arne