第一次发帖子出现了这个，是怎么了?

Discuz! info: MySQL Query Error

User: z422366368
Time: 2012-12-2 12:15pm
Script: /post.php

SQL: UPDATE [Table]members SET oltime= WHERE uid=14821197
Error: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'WHERE uid=14821197' at line 1
Errno.: 1064