Please Note:

1. To be fair to other users, queries run from SkyServer search tools are restricted in how long they can run and how much output they return, by timeouts and row limits. Please see the Query Limits help page. To run a query that is not restricted by a timeout or number of rows returned, please use the CasJobs batch query service.
2. For spatial queries using ra,dec limits, it is inefficient to use the constraints directly, e.g.:
   SELECT ... FROM PhotoTag
   WHERE (ra between ra1 AND ra2) AND (dec between dec1 AND dec2).
   The efficient way to do spatial queries is with the built-in functions that we provide, which use our HTM (Hierarchical Triangular Mesh) spatial indexing to speed up the search by an order of magnitude:
   SELECT ... FROM PhotoTag p, fGetObjFromRectEq(ra1,dec1,ra2,dec2) r
   WHERE p.objid=r.objid
   Please see the Optimizing Queries page and the Sample Queries page for more information.