SQL statement for retrieving random data

Source: Internet
Author: User

SQL statement for retrieving random data
In databases, data may be randomly extracted. of course, you can simply sort data by newid, but sometimes you need to extract the values of specific data, that is, the random extraction of cheating data. the method is as follows:

For example, the user information of 10 people is randomly extracted, but each time the user information of 'zhao Chunming 'must be included, and the displayed order is random. The SQL statement format is as follows:

Select * from
(
Select * from
(
Select * From t_user where c_name = 'zhao Chunming'
) Ta
Union all
Select * from
(
Select Top 9 * From t_user
Order by newid ()
) TB
) TC
Order by newid ()
 

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