如何编写单个查询查询数据

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你好， 如何使用单个查询更改数据?我创建了一个包含列ID和Gender的表.我已插入值，现在想交换性别值.原来的"M"将变为"F"，原来的"F"将变为"M". ID性别 1 M 2 F 3 M 4 F 5 M 6 F 更改输出后使用单查询 ID性别 1 F 2 M 3 F 4 M 5 F 6 M

Hello, how can I change the data using a single query? I''ve created one table with columns ID and Gender. I''ve inserted values and now want to interchange the gender values. What was ''M'' shall become ''F'' and what was ''F'' shall become ''M''. Id Gender 1 M 2 F 3 M 4 F 5 M 6 F AFTER CHANGE OUT PUT USE SINGLE QUERY Id Gender 1 F 2 M 3 F 4 M 5 F 6 M Thanks for your time!

推荐答案

您可以使用CASE WHEN构造执行相同的操作: msdn.microsoft/en-us/library/ms181765(v = SQL.90).aspx [ ^ ]. 例子: You can use the CASE WHEN construct to do the same: msdn.microsoft/en-us/library/ms181765(v=SQL.90).aspx[^]. An example: UPDATE dbo.GenderTable SET gender = (CASE WHEN 'F' THEN 'M' WHEN 'M' THEN 'F' END)

这适用于SQL-Server 2005& 2008. 问候，

—MRB

This works for SQL-Server 2005 & 2008. Regards,

—MRB

看看这个在2行中交换值SQL [ ^ ]，然后尝试将其应用于您的情况. Have a look at this Swap values in 2 rows SQL[^] and try applying it to your situation.

通过SQL更新语句. 检查这里: www.w3schools/sql/sql_update.asp [ ^ ] 基于此，您应该编写类似的内容: Via a SQL update statement. Check here: www.w3schools/sql/sql_update.asp[^] Based on this you should write something similar: UPDATE peoples SET sex='F' WHERE name='udaipal'

如果要在每个字段上都应用此属性，请不要使用WHERE子句. 干杯！

If you want to apply this on every single field, just don''t use the WHERE clause. Cheers!