查询更新列数据

Question

我正在尝试执行更新 ddbb 中多行的查询。我不确定是否会使用 UPDATE 或 ALTER table.

我有这样一个数据库：

id | enrol | status | courseid | sortorder | name | password
622  self      0        152          1              somepass
623  auto      0        153          1                  NULL
624  self      0        154          1              somepass
625  self      0        155          1              somepass
626  self      0        156          1                  NULL
627  auto      0        157          1              somepass
628  self      0        158          1              somepass
629  self      0        160          1              somepass
630  self      0        161          1              somepass
631  self      0        162          1                  NULL
632  self      0        163          1                  NULL

我想更新密码为 NULL 的所有行，我有这个查询

UPDATE mdl_enrol SET  password NULL WHERE  password IS NOT NULL and enrol = "self" ;

出于某种原因 phpMyAdmin returns :

#1064 - 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 'NULL WHERE password IS NOT NULL and enrol = "self"' at line 1

提前致谢！

Answer 1

设置密码值时只需添加赋值运算符("="):

UPDATE mdl_enrol 
SET  password = NULL 
WHERE  password IS NOT NULL and enrol = "self" ;