Export/Import Tool export error on bluehost space

I am using bluehost space, my products over 5000. I get a error xls when I export them.
Error: The SELECT would examine more than MAX_JOIN_SIZE rows; check your WHERE and use SET SQL_BIG_SELECTS=1 or SET SQL_MAX_JOIN_SIZE=# if the SELECT is okay

I tried run SET SQL_BIG_SELECTS=1 and run SET SQL_MAX_JOIN_SIZE=800000 in mysql database, but nothing happened
I asked customer service, they can not help me, they said:"you must modify your database". I do not know what it is meaning.

Anyone can help? how to export products data use this extension. or tell me how to modify in mysql.
thanks

Here is there helpdesk with the links to different ways to export: https://my.bluehost.com/cgi/help/search ... _started=1