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"UP"이라는 유사한 열이 있는 5개의 테이블에서 합계를 계산하는 MySQL 쿼리?

<시간/>

이를 위해 SUM()과 함께 UNION ALL을 사용하십시오. 5개의 테이블을 생성합시다 -

mysql> create table DemoTable1977
   (
   UP int
   );
Query OK, 0 rows affected (0.00 sec)
mysql> insert into DemoTable1977 values(10);
Query OK, 1 row affected (0.00 sec)
mysql> insert into DemoTable1977 values(20);
Query OK, 1 row affected (0.00 sec)
mysql> select * from DemoTable1977;
+------+
| UP   |
+------+
|   10 |
|   20 |
+------+
2 rows in set (0.00 sec)
mysql> create table DemoTable1978
   (
   UP int
   );
Query OK, 0 rows affected (0.00 sec)
mysql> insert into DemoTable1978 values(30);
Query OK, 1 row affected (0.00 sec)
mysql> select * from DemoTable1978;
+------+
| UP   |
+------+
|   30 |
+------+
1 row in set (0.00 sec)
mysql> create table DemoTable1979
   (
   UP int
   );
Query OK, 0 rows affected (0.00 sec)
mysql> insert into DemoTable1979 values(40);
Query OK, 1 row affected (0.00 sec)
mysql> select * from DemoTable1979;
+------+
| UP   |
+------+
|   40 |
+------+
1 row in set (0.00 sec)
mysql> create table DemoTable1980
   (
   UP int
   );
Query OK, 0 rows affected (0.00 sec)
mysql> insert into DemoTable1980 values(50);
Query OK, 1 row affected (0.00 sec)
mysql> select * from DemoTable1980;
+------+
| UP   |
+------+
|   50 |
+------+
1 row in set (0.00 sec)
mysql> create table DemoTable1981
   (
   UP int
   );
Query OK, 0 rows affected (0.00 sec)
mysql> insert into DemoTable1981 values(60);
Query OK, 1 row affected (0.00 sec)
mysql> select * from DemoTable1981;
+------+
| UP   |
+------+
|   60 |
+------+
1 row in set (0.00 sec)

다음은 "UP"이라는 단일 열이 있는 5개의 테이블에서 합계를 계산하는 쿼리입니다. -

mysql> select  sum(TotalSum)
   from    (
      select sum(UP) as TotalSum
      from DemoTable1977
      union all
      select sum(UP)
      from DemoTable1978
      union all
      select sum(UP)
      from DemoTable1979
      union all
      select sum(UP)
      from DemoTable1980
      union all
      select sum(UP)
      from DemoTable1981
   
      ) tbl;

이것은 다음과 같은 출력을 생성합니다 -

+---------------+
| sum(TotalSum) |
+---------------+
|           210 |
+---------------+
1 row in set (0.00 sec)