看看曾经的私密日志。原来自己之前被非常多小而简单的问题困惑过。

看着那时候我们还是新手中的新手做的备忘笔记！

事实上就是用了Oracle的统计函数而已！

曾经的日记（看样子应该是曾经公司的源代码，呵呵……）例如以下：勿喷！

对多数据进行分组排序后取每组第一条记录：

SELECT *

  FROM (

       SELECT ROW_NUMBER() OVER(

       PARTITION BY  ZA40011_3.URIAGE_DENPYO_NO,ZA40011_3.URIAGE_DENPYO_ROW_NO

       ORDER BY  ZA40011_3.KAKUTEI_SURYO_CS,

                  ZA40011_3.KAKUTEI_SURYO_BL,

                  ZA40011_3.KAKUTEI_SURYO_BT,

                  ZA40011_3.SYUKKA_SHIJI_NO,

                  ZA40011_3.SYUKKA_SHIJI_ROW_NO  DESC) LEV,

                ZA40011_3 .*

       FROM  WT_001_ZA40011_22070_2 ZA40011_2,

             WT_001_ZA40011_22070_3 ZA40011_3,

             JT_GYOMU_URIAGE_DETAIL URIAGE_DETAIL

       WHERE

       ZA40011_2.KAISYA_CODE = URIAGE_DETAIL.KAISYA_CODE

           AND ZA40011_2.URIAGE_DENPYO_NO = URIAGE_DETAIL.URIAGE_DENPYO_NO

           AND ZA40011_2.URIAGE_DENPYO_ROW_NO = URIAGE_DETAIL.ROW_NO

           AND URIAGE_DETAIL.KAISYA_CODE = ZA40011_3.KAISYA_CODE

           AND URIAGE_DETAIL.URIAGE_DENPYO_NO = ZA40011_3.URIAGE_DENPYO_NO

           AND URIAGE_DETAIL.ROW_NO = ZA40011_3.URIAGE_DENPYO_ROW_NO

           AND ZA40011_3.KEPPIN_RIYU_CODE IS NOT NULL

        )

 WHERE LEV = 1

-- ORDER BY KAKUTEI_SURYO_CS DESC