使用MySQL。我需要根据以下条件为每组storeID + profitCenter提取一条记录:
1)如果组有一个活动记录(active = 1),请选择该记录
2)如果组没有活动记录,请选择最近的(max(id))
3)如果组有多个活动记录,请选择最近的活动记录
样本表: (为清晰起见,添加了空白行)
ID | storeID | profitCenter | active
--------------------------------------
1 | X | 1 | 1
2 | X | 1 | 0
3 | X | 1 | 0
4 | X | 2 | 0
5 | X | 2 | 1
6 | X | 3 | 0
7 | X | 3 | 0
8 | X | 3 | 0
9 | X | 4 | 1
10 | X | 4 | 1
11 | X | 4 | 0
12 | X | 5 | 1
13 | X | 6 | 0
期望的结果:
ID | storeID | profitCenter | active
------------------------------------------
1 | X | 1 | 1
5 | X | 2 | 1
8 | X | 3 | 0
10 | X | 4 | 1
12 | X | 5 | 1
13 | X | 6 | 0
单个查询会很棒,但我认为由于其复杂性,我需要在存储过程中执行此操作。我需要将记录写入新表,以便我可以在连接中使用它等。到目前为止,我真正得到的只是......
...一个简单的查询来拉动"单个"这样的记录....
SELECT * FROM table GROUP BY storeID, profitCenter HAVING count(*) = 1 AND active = 1
UNION
SELECT * FROM table GROUP BY storeID, profitCenter HAVING count(*) = 1 AND active = 0
......产生......
ID | storeID | profitCenter | active
------------------------------------------
12 | X | 5 | 1
13 | X | 6 | 0
然后我可以做......
SELECT sum(active),tmult.* FROM
(SELECT t.* FROM t LEFT JOIN
(SELECT t.* FROM t GROUP BY storeID, profitCenter HAVING count(*) = 1 AND active = 1
UNION
SELECT t.* FROM t GROUP BY storeID, profitCenter HAVING count(*) = 1 AND active = 0) tsing
ON t.id = tsing.id
WHERE tsing.id IS NULL) tmult
GROUP BY storeid, profitCenter
HAVING sum(active)=1;
...为每个只有一条活动记录的组提供活动记录:
ID | storeID | profitCenter | active
--------------------------------------
1 | X | 1 | 1
5 | X | 2 | 1
没有活动记录或多个活动记录的群组我甚至无法开始弄明白。
我采取了正确的方法吗?我应该在SQL中尝试这个吗?我可以写一个脚本来做,但我希望不必走这条路。
任何建议都将受到赞赏。
答案 0 :(得分:1)
我相信这样的事情应该这样做:
select
ifnull(max(active_records.id), max(all_records.id)) id,
all_records.store_id,
all_records.profit_center,
if(max(active_records.id) is null, 0, 1) active
from
store all_records
left outer join store active_records on all_records.id = active_records.id and active_records.active = 1
group by
all_records.store_id,
all_records.profit_center
;
ddl和insert的完整示例如下所示:
create table store (
id int,
store_id varchar(64),
profit_center int,
active bit
);
insert into store values ( 1 , 'X' , 1 , 1);
insert into store values ( 2 , 'X' , 1 , 0);
insert into store values ( 3 , 'X' , 1 , 0);
insert into store values ( 4 , 'X' , 2 , 0);
insert into store values ( 5 , 'X' , 2 , 1);
insert into store values ( 6 , 'X' , 3 , 0);
insert into store values ( 7 , 'X' , 3 , 0);
insert into store values ( 8 , 'X' , 3 , 0);
insert into store values ( 9 , 'X' , 4 , 1);
insert into store values (10 , 'X' , 4 , 1);
insert into store values (11 , 'X' , 4 , 0);
insert into store values (12 , 'X' , 5 , 1);
insert into store values (13 , 'X' , 6 , 0);
select
ifnull(max(active_records.id), max(all_records.id)) id,
all_records.store_id,
all_records.profit_center,
if(max(active_records.id) is null, 0, 1) active
from
store all_records
left outer join store active_records on all_records.id = active_records.id and active_records.active = 1
group by
all_records.store_id,
all_records.profit_center
;
+ ------- + ------------- + ------------------ + ----------- +
| id | store_id | profit_center | active |
+ ------- + ------------- + ------------------ + ----------- +
| 1 | X | 1 | 1 |
| 5 | X | 2 | 1 |
| 8 | X | 3 | 0 |
| 10 | X | 4 | 1 |
| 12 | X | 5 | 1 |
| 13 | X | 6 | 0 |
+ ------- + ------------- + ------------------ + ----------- +
6 rows
答案 1 :(得分:0)
您可以使用union all
尝试此操作。
SELECT *
FROM TABLE
WHERE (storeID, profitCenter, Id) IN (
SELECT storeID, profitCenter, MAX(case when active=1 then id end) as maxid
FROM table
GROUP BY storeID, profitCenter
HAVING SUM(active) >= 1
UNION ALL
SELECT storeID, profitCenter, MAX(id)
FROM table
GROUP BY storeID, profitCenter
HAVING SUM(active) = 0
)