Question

我的Oracle数据库中有以下表格

TopCode BottomCode  Totalpeep
A   ABC123      100
B   BED456           45

我想要一个能够根据Totalpeep / 20分割行的查询，例如A组有5组，B组有3组，即使Totalpeep小于20组，也必须有一组

TopCode  BottomCode  Grp
A        ABC123      A1
A        ABC123      A2
A        ABC123      A3
A        ABC123      A4
A        ABC123      A5
B        BED456      B1
B        BED456      B2
B        BED456      B3

Answer 1

使用connect方式轻松实现：

with sample_data (TopCode, BottomCode, Totalpeep) as (select 'A', 'ABC123', 100 from dual union all
                                                      select 'B', 'BED456', 45 from dual)
select topcode,
       bottomcode,
       topcode||level grp
from   sample_data
connect by prior topcode = topcode
           and prior dbms_random.value is not null
           and level <= ceil(totalpeep/20);

TOPCODE BOTTOMCODE GRP                                      
------- ---------- ----
A       ABC123     A1
A       ABC123     A2
A       ABC123     A3
A       ABC123     A4
A       ABC123     A5
B       BED456     B1
B       BED456     B2
B       BED456     B3

Answer 2

我会给你一个方法：

划分列值会提供您需要拆分的行数。
然后进一步除以该计数将其分为相等数量的桶。其余的是 ROW GENERATOR 方法。

测试案例

SQL> CREATE TABLE t(
  2  topcode VARCHAR2(10),
  3  totalpeep NUMBER);

Table created.

SQL>
SQL> INSERT INTO t VALUES('A', 100);

1 row created.

SQL> INSERT INTO t VALUES('B', 45);

1 row created.

SQL>
SQL> SELECT * FROM t;

TOPCODE     TOTALPEEP
---------- ----------
A                 100
B                  45

SQL>

因此，SQL根据计数创建相同数量的桶：

SQL> WITH DATA AS
  2    ( SELECT t.*, t.totalpeep/20 wt_bucket  FROM t )
  3  SELECT topcode, topcode||level
  4  FROM DATA
  5    CONNECT BY LEVEL          <= wt_bucket
  6  AND PRIOR topcode            = topcode
  7  AND PRIOR DBMS_RANDOM.VALUE IS NOT NULL
  8  /

TOPCODE    TOPCODE||LEVEL
---------- --------------------------------------------
A          A1
A          A2
A          A3
A          A4
A          A5
B          B1
B          B2

7 rows selected.

SQL>

即使Totalpeep小于20，也必须有一组

在这种情况下，还应考虑未使用的剩余铲斗：

SQL> WITH DATA AS
  2    ( SELECT t.*, t.totalpeep/20 wt_bucket  FROM t )
  3  SELECT topcode, topcode||level
  4  FROM DATA
  5    CONNECT BY LEVEL          <= ceil(wt_bucket)
  6  AND PRIOR topcode            = topcode
  7  AND PRIOR DBMS_RANDOM.VALUE IS NOT NULL
  8  /

TOPCODE    TOPCODE||LEVEL
---------- --------------------------------------------
A          A1
A          A2
A          A3
A          A4
A          A5
B          B1
B          B2
B          B3

8 rows selected.

SQL>

因此，对于分割后值不是整数的组，您也可以考虑它们。

根据值拆分行

2 个答案: