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从条件group by返回多行,不带并集

sqlite sql

Abhishek Ginani · 技术社区 · 6 年前

我正在尝试在sqlite db中构建一个支持条件group by的查询。

以下是我迄今为止所做的尝试:

SELECT 
      case 
       when A>1 AND B>1 THEN 1
       when X>1 AND Y>1 THEN 2
       when C>1 AND D>1 THEN 3
      END AS data_grp,
     SUM(col1) AS col1,
     SUM(col2) AS col2
FROM tbl
GROUP BY data_grp;

如果一次只有一个案例是正确的,那么这就非常有效。如果一行中有多个事例为真,则返回第一个事例,而不是所有令人满意的组。

我试过这个 union 它工作得很好,但速度很慢。有没有其他方法可以用这个条件组快速获取结果。

示例数据和预期结果:

DROP TABLE IF EXISTS  tbl;
CREATE TABLE tbl
(
    A INT,
    B INT,
    C INT,
    D INT,
    X INT,
    Y INT,
    col1 int,
    col2 int

);

INSERT INTO tbl(A,B,C,D,X,Y,col1,col2) values (2,3,0,0,0,0,5,10);
INSERT INTO tbl(A,B,C,D,X,Y,col1,col2) values (0,0,0,0,8,10,3,2);
INSERT INTO tbl(A,B,C,D,X,Y,col1,col2) values (5,4,4,9,0,0,3,2);

    SELECT 
          case 
           when A>1 AND B>1 THEN 1
           when X>1 AND Y>1 THEN 2
           when C>1 AND D>1 THEN 3
          END AS data_grp,
         SUM(col1) AS col1,
         SUM(col2) AS col2
    FROM tbl
    GROUP BY data_grp;

查询输出:

"1" "8" "12"
"2" "3" "2"

预期输出:

"1" "8" "12"
"2" "3" "2"
"3" "3" "2"

2 回复 | 直到 6 年前

Peeyush 6 年前

GROUP BY

WITH RECURSIVE
  cnt(x) AS (
     SELECT 1
     UNION ALL
     SELECT x+1 FROM cnt
      LIMIT 3
  )
SELECT x as data_grp, sum(col1), sum(col2)
FROM cnt, 
      (SELECT 
          case when A>1 AND B>1 THEN 1  ELSE 0 END as dg1,
          case when X>1 AND Y>1 THEN 2 ELSE 0 END as dg2,
          case when C>1 AND D>1 THEN 3 ELSE 0 END as dg3,
          col1, col2
        FROM tbl) t WHERE x=dg1 or x=dg2 or x=dg3
GROUP BY x

Gordon Linoff 6 年前

SELECT ( (CASE WHEN A > 1 AND B > 1 THEN '1' ELSE '' END) ||
         (CASE WHEN X > 1 AND Y > 1 THEN '2' ELSE '' END) ||
         (CASE WHEN C > 1 AND D > 1 THEN '3' ELSE '' END)
       ) AS data_grp,
       SUM(col1) AS col1, SUM(col2) AS col2
FROM tbl
GROUP BY data_grp;

SELECT ( (CASE WHEN A > 1 AND B > 1 THEN '1' ELSE '0' END) ||
         (CASE WHEN X > 1 AND Y > 1 THEN '1' ELSE '0' END) ||
         (CASE WHEN C > 1 AND D > 1 THEN '1' ELSE '0' END)
       ) AS data_grp,

data_grp

SELECT SUM(CASE WHEN A > 1 AND B > 1 THEN col1 ELSE 0 END) as sum1_1,
       SUM(CASE WHEN X > 1 AND Y > 1 THEN col1 ELSE 0 END) as sum1_2,
       SUM(CASE WHEN C > 1 AND D > 1 THEN col1 ELSE 0 END) as sum1_3,
       SUM(CASE WHEN A > 1 AND B > 1 THEN col2 ELSE 0 END) as sum2_1,
       SUM(CASE WHEN X > 1 AND Y > 1 THEN col2 ELSE 0 END) as sum2_2,
       SUM(CASE WHEN C > 1 AND D > 1 THEN col2 ELSE 0 END) as sum2_3
FROM tbl;