oracle - Oracle中按分组列自动编号

Question

我的问题是否有任何 oracle 声明。

例如。TableA 有 2 列：columnA and columnB

ColumnA    ColumnB
-------------------
 A         WA
 A         WA
 B         WA
 B         WA
 C         WA
 A         CA
 A         CA
 B         CA
 B         CA
 C         CA

我想要的是：自动编号Group by ColumnA

Auto  ColumnA  ColumnB
-----------------------
1     A        WA
2     A        WA
3     A        CA
4     A        CA
1     B        WA
2     B        WA
3     B        CA
4     B        CA
1     C        WA
2     C        CA

Answer 1

您可以为此使用ROW_NUMBER函数。按您的 columnA 分组并指定一些 order by 子句。

SELECT ROW_NUMBER () OVER (PARTITION BY columnA ORDER BY columnB) as "auto",
       columnA, columnB
  FROM table;