为什么你不应该使用mysql_fetch_assoc超过1次？

Question

Some people say you should not use mysql_fetch_assoc more than one time, why is that?

e.g.: I want to display two tables one with users who paid for membership, other with users who did not, so instead of querying database 2 times I query it one time and get $result variable with both types of users then I run loop mysql_fetch_assoc and see if list['membership'] = 'paid' then echo ...

Second time I loop loop mysql_fetch_assoc and see if list['membership'] = 'free' then echo ...

What uses less resources considering I got about equal amount of users who registered and unregistered.

Answer 1

When someone says you can't call mysql_fetch_assoc() twice, they mean against the same resource. The resource result you pass in to mysql_fetch_assoc() is done by reference. You'll need to reset the position of the pointer before you can use mysql_fetch_assoc() a second time.

EDIT: And to do so, try using mysql_data_seek().