在MySQL中用IF条件更新... [英] Do update with IF condition... in MySQL

问题描述

嗨！

如果且仅当我的

条件为真时，任何人都知道是否可以进行更新。

示例：


在MYTABLE中我有三列，如下：

ID（INT），PUBLISH（ENUM（Y，N） ），密码（VARCHAR（10））

这就是我想要做的事情：

用id = 333更新tablerow，SET publish =''是'如果密码='''xxx''


我正在尝试使用MySQL表达式IF（expr1，expr2，expr3）。但这个

真的不行！


如果可以在expr1中设置SELECT语句，它可以工作，

返回NULL或EmptyString。然后如果NULL DO（执行）expr2 ELSE

DO（执行）expr3


像这样：IF（SELECT * FROM mytable WHERE id = 333 AND

PASSWORD =''xxx''，UPDATE mytable SET publish =''N''WHERE id = 333，UPDATE

mytable SET publish =''Y''WHERE id = 333）


任何想法？

Hi!
Anyone knows if it''s possible to do an update if, and only if my
condition is TRUE.

Example:

In MYTABLE I have three columns, like this:
ID(INT), PUBLISH(ENUM(Y,N)), PASSWORD(VARCHAR(10))

This is what I want to do:
UPDATE the tablerow with id=333, SET publish=''Y'' IF password=''xxx''

I was trying out the MySQL-expression "IF(expr1,expr2,expr3)" but this
really doesn''t do it!

It could work if it was possible to set a SELECT statement in expr1,
returning NULL or EmptyString. Then if NULL DO(execute) expr2 ELSE
DO(execute) expr3

Like this: IF(SELECT * FROM mytable WHERE id=333 AND
PASSWORD=''xxx'',UPDATE mytable SET publish=''N'' WHERE id=333, UPDATE
mytable SET publish=''Y'' WHERE id=333 )

Any ideas?

推荐答案

JP写道：

J.P wrote:

这就是我想要做的事情：
用id = 333更新tablerow，SET发布=''Y''如果密码='''xxx''

This is what I want to do:
UPDATE the tablerow with id=333, SET publish=''Y'' IF password=''xxx''

＃仅当密码和id匹配时才会更新行。

更新yourtablename set publish =''Y''其中id = 333且password =''xxx'';

# This will update row only if the password and id match.
update yourtablename set publish=''Y'' where id=333 and password=''xxx'';

JP写道：

J.P wrote:

这就是我想要做的：
用id = 333，SET更新tablerow publish =''Y''如果密码='''xxx''

This is what I want to do:
UPDATE the tablerow with id=333, SET publish=''Y'' IF password=''xxx''

＃这将更新行o nly如果密码和id匹配。

更新yourtablename set publish =''Y''，其中id = 333，密码=''xxx'';

# This will update row only if the password and id match.
update yourtablename set publish=''Y'' where id=333 and password=''xxx'';

JP写道：

J.P wrote:

这就是我想要做的事情：
用id = 333更新tablerow，SET publish =''Y''IF password = ''xxx''

This is what I want to do:
UPDATE the tablerow with id=333, SET publish=''Y'' IF password=''xxx''

＃只有在密码和id匹配时才会更新行。

update yourtablename set publish =''Y ''id = 333，密码=''xxx'';

# This will update row only if the password and id match.
update yourtablename set publish=''Y'' where id=333 and password=''xxx'';

这篇关于在MySQL中用IF条件更新...的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！