ROWNUM在Oracle中 [英] ROWNUM IN ORACLE

问题描述

我想检索ORACLE 9i中第4位的记录. 我可以在WHERE子句中比较ROWNUM = 4吗?

I want to retrive record at 4th position in ORACLE 9i. Can I compare ROWNUM=4 in the WHERE clause??

推荐答案

不，在评估WHERE子句之后分配了ROWNUM，因此它不能跳过"行数一到三.

No, ROWNUM is assigned after the WHERE clause is evaluated, so it cannot "skip" rownum one to three.

此外，它是在排序之前分配的.

Furthermore, it is assigned BEFORE sorting.

这是Oracle最烦人的功能".他们确实需要实现LIMIT/OFFSET.

This is the most annoying "feature" of Oracle. They really need to implement LIMIT/OFFSET.

您需要做类似的事情

  select * from (
      select a.*, rownum rn from (
         select the_data from the_table order by the_order 
      ) a where rownum < 5
  ) where rn = 4

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