SQL group_by查詢

-4

我有一個表名用戶。假設在我有以下字段的表：SQL group_by查詢

用戶ID，UUID1，UUID2

我想建立下面的SQL查詢將返回：。數行既包括同一UUID1和UUID2的。不是UUID1等於UUID2，而是包含兩者（GROUP BY）的行數，另外行數包含UUID1或UUID2（單獨，無分組）。

所以我想有一臺輸出如下： UUID1，UUID2，Number_of_Rows_Contain_both，Number_Of_Rows_Contains_Only_Only_One

任何想法，我怎麼能產生這樣的查詢？

來源

2016-05-31 Nuno_147

添加一些樣本表數據，和預期的結果。 – jarlh

樣本數據請參閱 – theDbGuy

另請參見：您正在使用哪些DBMS？ –

希望這是你在aksing什麼：

select 
user_id, 
sum 
(case when uuid1 is not null and uuid2 is not null then 1 else 0 end) both_uuid_avlbl, 
sum 
(case when uuid1 is not null then 1 else 0 end) uuid1_avlbl, 
sum 
(case when uuid2 is not null then 1 else 0 end) uuid2_avlbl 
from sample group by user_id;

下面是DDL腳本我用上面的查詢：

create table sample as (user_id number(10),uuid1 number(10),uuid2 number(10)); 
    Insert into sample (USER_ID,UUID1,UUID2) values (1,2,2); 
Insert into sample (USER_ID,UUID1,UUID2) values (2,3,2); 
Insert into sample (USER_ID,UUID1,UUID2) values (3,1,1); 
Insert into sample (USER_ID,UUID1,UUID2) values (4,1,2); 
Insert into sample (USER_ID,UUID1,UUID2) values (5,2,0); 
Insert into sample (USER_ID,UUID1,UUID2) values (8,null,2); 
Insert into sample (USER_ID,UUID1,UUID2) values (7,null,null); 
Insert into sample (USER_ID,UUID1,UUID2) values (6,null,2); 
Insert into sample (USER_ID,UUID1,UUID2) values (3,null,1); 
Insert into sample (USER_ID,UUID1,UUID2) values (1,3,2); 
Insert into sample (USER_ID,UUID1,UUID2) values (1,null,2); 
Insert into sample (USER_ID,UUID1,UUID2) values (5,3,0); 
Insert into sample (USER_ID,UUID1,UUID2) values (5,3,null); 
insert into sample (user_id,uuid1,uuid2) values (5,null,null);

我用的Oracle 11g。

來源

2016-05-31 13:12:00 theDbGuy

可能會將此方法稱爲「條件聚合」儘管我不知道是否需要user_ID和group by，因爲OP僅詢問行數，並且「單獨，無分組」 – xQbert

如果不需要，則取出分組。讓事情變得容易理解 – theDbGuy

你的結果，你可以去這樣的：

declare @both INT 
    declare @a INT 
    declare @b INT 
    declare @c INT 
    select @both = count(*) from users where UUID1 is not null and UUID2 is not null 
    select @a = count(*) from users where UUID1 is not null and UUID2 is null 
    select @b = count(*) from users where UUID1 is null and UUID2 is not null 
    select @c = count(*) from users where UUID1 is null and UUID2 is null 
    Select @both as BothCount,@a AS UUID1Count,@b AS UUID2Count,@c AS Bothnull

來源

2016-05-31 13:13:56

讓我把我對你的問題的理解第一; 表格格式如下;

user_id,UUID1, UUID2 
1 a a 
2 a b 
3 b b 
4 b c 
5 d c

並且您正在查找的此類輸入樣本的輸出如下所示;

可能的解決方案是;

SELECT UUID, sum(SAME) SAME, sum(DIFFERENT - SAME) DIFFERENT 
FROM (
    select a.UUID, 
     case when (a.UUID = t.UUID1 and a.UUID = t.UUID2) THEN 1 else 0 end SAME, 
     case when a.UUID = t.UUID1 or a.UUID = t.UUID2 THEN 1 else 0 end DIFFERENT 
    from 
    (
     select distinct UUID1 as UUID 
     from THE_TABLE 

     UNION 

     select distinct UUID2 as UUID 
     from THE_TABLE 
    ) a, THE_TABLE t 
) GROUP BY UUID

測試與DB2 v 10.5.5

來源

2016-05-31 13:22:57 tafa

SQL group_by查詢

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