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  • SQL 查询唯一数据/查询重复数据

    //SQL 查询唯一数据/查询重复数据

    --select  *  from MEMBER_FAVORITE where ROW_ID (not) in(
    --select MAX(ROW_ID) from MEMBER_FAVORITE group by FAVORITE_TYPE,BLOCK_ID,MEMBER_ID
    --)

    1.FAVORITE_TYPE,BLOCK_ID,MEMBER_ID 唯一的标准。

    2.无 not ,查询结果是 上述信息 显示唯一数据。

    3.有 not ,  是预备删除的重复数据。

    //   row number over 分页 

           condition = @" SELECT * FROM(
                                                select TOP " + (skip + count) + @"  
                                                *,
                                                ROW_NUMBER()
                                                 OVER(" + sortSql + @") AS ROWID
                                                from BASE_BLOCK block 
                                                where  ... order by ...
                                                ) AS TEMP1
                                                WHERE ROWID>" + skip;

    --ROW_NUMBER() 就是生成一个有顺序的行号,而他生成顺序的标准,就是后面紧跟的OVER(ORDER BY ID)
    --还必须添加OVER语句以便告诉SQL Server你希望怎样添加行序号,排序方式唯一,否则你会找不到你要的结果。

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  • 原文地址:https://www.cnblogs.com/chenly-index/p/3455416.html
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