Xmatch with ls_dr9sv.tractor_n produces error

Question

When using the Xmatch tool, I continually get this error when trying to cross-match my uploaded table against the ls_dr9sv.tractor_n catalog.

Error: column g.null does not exist LINE 1: ...sv.tractor_n AS g WHERE 't'=q3c_join(o.ra, o.dec, g.null, g.... ^

Answer 1

After you select 'ls_dr9sv.tractor_n' table, it takes a while to load the 'ra' column box and 'dec' column box below the table list. If you press 'submit' button before the 'ra' column and 'dec' column appear, then the 'ra' and 'dec' for the 2nd table are not selected, so you would see this error.