Hi Elena, thanks for reaching out. Downloading the entire nsc_dr2.object table will be difficult -- it's very big. We have done that on occasion, but for other institutions, and it required that they have access to Globus configured.
For your cross-match, would it help if you could use the pre-crossmatched table nsc_dr2.x1p5__object__gaia_dr2__gaia_source ? It's the xmatch of nsc_dr2.object against gaia_dr2.gaia_source, with a matching radius of 1.5 arcsec, keeping only the nearest match, and not keeping rows without a match. A JOIN operation on this table is much faster than a dedicated cross-match over the entire NSC DR2...
Other tips on cutting down the size in your queries:
- only request a few columns, not '*'
- experiment while using subqueries (as you do) and LIMIT statements
- go in slices of RA maybe?
Also, please feel free to send us a minimal workflow example that shows what you are trying to achieve, and where it fails. We will of course try to help. You can email to email@example.com