日期:2014-05-17  浏览次数:21136 次

sql 检索问题
编号1 编号2 数量 
1 1 1
1 2 1
1 3 1
2 4 1
2 5 1
2 6 1
3 7 1
3 8 1
4 9 1
4 10 1

传入一个参数,按照编号一排序,然后从小到大依次将“数量”字段加和,获取加和刚好大于传入参数的最少的前几项数据,例如:
传入参数 3 得到结果

1 1 1
1 2 1
1 3 1

传入参数 4 得到结果

1 1 1
1 2 1
1 3 1
2 4 1
2 5 1
2 6 1


传入参数 7 得到结果

1 1 1
1 2 1
1 3 1
2 4 1
2 5 1
2 6 1
3 7 1
3 8 1

------解决方案--------------------
SQL code
select *
  from ttt
 where rownum < 3
union
select *
  from ttt
 where a = (select 编号1 from (select 编号1, rownum n from ttt) where n = 3)

------解决方案--------------------
LZ等于7的情况应该会SELECT出来全部记录。 1+2+3+4+5+6 = 21
SQL code
TRY IT ..
SQL> SELECT * FROM TEST_NUM;

      NUM1       NUM2        QTY
---------- ---------- ----------
         1          1          1
         1          2          1
         1          3          1
         2          4          1
         2          5          1
         2          6          1
         3          7          1
         3          8          1
         4          9          1
         4         10          1

10 rows selected

-- ENTER_NUM = 3
SQL> SELECT *
  2    FROM TEST_NUM
  3   WHERE NUM2 <= (SELECT SUM(DECODE(SIGN(&ENTER_NUM - NUM2), 1, NUM2, 0))
  4                    FROM TEST_NUM);

      NUM1       NUM2        QTY
---------- ---------- ----------
         1          1          1
         1          2          1
         1          3          1

-- ENTER_NUM = 4
SQL> SELECT *
  2    FROM TEST_NUM
  3   WHERE NUM2 <= (SELECT SUM(DECODE(SIGN(&ENTER_NUM - NUM2), 1, NUM2, 0))
  4                    FROM TEST_NUM);

      NUM1       NUM2        QTY
---------- ---------- ----------
         1          1          1
         1          2          1
         1          3          1
         2          4          1
         2          5          1
         2          6          1

6 rows selected

-- ENTER_NUM = 7
SQL> SELECT *
  2    FROM TEST_NUM
  3   WHERE NUM2 <= (SELECT SUM(DECODE(SIGN(&ENTER_NUM - NUM2), 1, NUM2, 0))
  4                    FROM TEST_NUM);

      NUM1       NUM2        QTY
---------- ---------- ----------
         1          1          1
         1          2          1
         1          3          1
         2          4          1
         2          5          1
         2          6          1
         3          7          1
         3          8          1
         4          9          1
         4         10          1

10 rows selected

SQL>

------解决方案--------------------
SQL code

select *
  from table
 where rownum <= (select rr
                    from (select sum(数量) over(partition by 1 order by rownum) rn,
                                 rownum rr
                            from table t
                           order by 编号1, 编号2)
                   where rn > [color=#FF0000]10[/color]
                     and rownum = 1)
 order by 编号1, 编号2