do u have a code example for us?
Some tips i can tell u out of mind:
-mysql_free_result after every SELECT query
-Optimize your string/query/row lengths
-Optimize your mysql tables (creating only adjusted fields/columns=> int and vchars, create only the string lenght you really need.)
-Use sscanf to split rows/results.
DONT use a saving system on OnPlayerUpdate (u may laught but ive already seen this multiple times
)
//edit:
Use the profiler plugin to be sure mysql causes the lag!