Code:
UPDATE spawnentry SET spawngroupID=spawngroupID+331999 WHERE (spawngroupID>=1328001 AND spawngroupID<=1328268);
How does this work?
the bottom number in the original spawngroupID is 1328001 if you add 331999 to it, you get 1660000. next number (as per code mentioned) will be 1328001; add 331999 , you get 1660001, all get changed by one up to 1328268 ( last should be 1660268 ).