我的问题可以归结为：
我有四个桌子
CREATE TABLE table_1 (
table_1_id int,
table_1_name varchar(45),
table_1_team varchar(45)
);
CREATE TABLE table_2 (
table_2_id int,
table_1_id int,
table_2_name varchar(45)
);
CREATE TABLE table_3 (
table_4_id int,
table_1_id int
);
CREATE TABLE table_4 (
table_4_id int,
table_4_name varchar(45)
);
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (1, 't1-name-1-t4', 'team1');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (2, 't1-name-2-t1', 'team1');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (3, 't1-name-3-t2', 'team1');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (4, 't1-name-4', 'team dont-regard-me-1');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (5, 't1-name-5-t1', 'team2');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (6, 't1-name-6-t2', 'team2');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (7, 't1-name-7', 'team dont-regard-me-2');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (8, 't1-name-8-t4', 'team3');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (9, 't1-name-9-t1', 'team3');
INSERT INTO table_1 (table_1_id, table_1_name, table_1_team) VALUES (10, 't1-name-10-t2', 'team3');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (1, 3, 't2-name-1');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (2, 3, 't2-name-2');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (3, 6, 't2-name-3');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (4, 6, 't2-name-4');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (5, 6, 't2-name-5');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (6, 10, 't2-name-6');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (7, 10, 't2-name-7');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (8, 66,'t2-name-8');
INSERT INTO table_2 (table_2_id, table_1_id, table_2_name) VALUES (9, 77, 't2-name-9');
INSERT INTO table_3 (table_4_id, table_1_id) VALUES (1, 1);
INSERT INTO table_3 (table_4_id, table_1_id) VALUES (2, 1);
INSERT INTO table_3 (table_4_id, table_1_id) VALUES (3, 1);
INSERT INTO table_3 (table_4_id, table_1_id) VALUES (6, 1);
INSERT INTO table_3 (table_4_id, table_1_id) VALUES (7, 8);
INSERT INTO table_3 (table_4_id, table_1_id) VALUES (8, 8);
INSERT INTO table_3 (table_4_id, table_1_id) VALUES (9, 8);
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (1, 't4-name-1');
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (2, 't4-name-2');
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (3, 't4-name-3');
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (4, 't4-name-4');
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (5, 't4-name-5');
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (6, 't4-name-6');
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (7, 't4-name-7');
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (8, 't4-name-8');
INSERT INTO table_4 (table_4_id, table_4_name) VALUES (9, 't4-name-9');
和我要合并的三个选择查询
SELECT
t1.table_1_id AS t1_id,
t1.table_1_name AS t1_name
FROM
table_1 t1
WHERE
t1.table_1_team IN ('team1', 'team2', 'team3') AND
t1.table_1_id NOT IN (1,3,6,8,10);
SELECT
t1.table_1_id AS t1_id,
t4.table_4_id AS t4_id,
t4.table_4_name AS t4_name
FROM
table_4 t4,
table_1 t1,
table_3 t3
WHERE
t1.table_1_id IN (1,3,6,8,10) AND
t3.table_1_id = t1.table_1_id AND
t3.table_4_id = t4.table_4_id;
SELECT
t1.table_1_id,
t2.table_2_id,
t2.table_2_name
FROM
table_2 t2,
table_1 t1
WHERE
t1.table_1_id IN (1,3,6,8,10) AND
t1.table_1_id = t2.table_1_id;
我想要的输出如下：
| t1_id | t1_name | t1_team | t2_id | t2_name | t4_id | t4_name |
+-------+--------------+---------+--------+-----------+--------+-----------+
| 1 | t1-name-1-t4 | team1 | (null) | (null) | 6 | t4-name-6 |
| 1 | t1-name-1-t4 | team1 | (null) | (null) | 1 | t4-name-1 |
| 1 | t1-name-1-t4 | team1 | (null) | (null) | 3 | t4-name-3 |
| 1 | t1-name-1-t4 | team1 | (null) | (null) | 2 | t4-name-2 |
| 2 | t1-name-2-t1 | team1 | (null) | (null) | (null) | (null) |
| 3 | t1-name-3-t2 | team1 | 1 | t2-name-1 | (null) | (null) |
| 3 | t1-name-3-t2 | team1 | 2 | t2-name-2 | (null) | (null) |
| 5 | t1-name-5-t1 | team2 | (null) | (null) | (null) | (null) |
| 6 | t1-name-6-t2 | team2 | 4 | t2-name-4 | (null) | (null) |
...
这是我到目前为止得到的：
SELECT
t1.table_1_id AS t1_id,
t1.table_1_name AS t1_name,
linkTable1.table_2_id AS t2_id,
linkTable1.table_2_name AS t2_name,
linkTable2.table_4_id AS t4_id,
linkTable2.table_4_name AS t4_name
FROM
table_1 t1
LEFT JOIN (
SELECT
table_2.table_2_id,
table_2.table_2_name,
table_2.table_1_id
FROM
table_2) linkTable1
ON
t1.table_1_id = linkTable1.table_1_id
LEFT JOIN (
SELECT
table_3.table_1_id,
table_4.table_4_id,
table_4.table_4_name
FROM
table_4
INNER JOIN
table_3
ON
table_4.table_4_id = table_3.table_4_id) linkTable2
ON
t1.table_1_id = linkTable2.table_1_id;
但是这种方法导致不必要的行：
...
| 4 | t1-name-4 |team dont-regard-me-1 | (null) | (null) | (null) | (null) |
...
所以我必须找到一种方法来正确整合where子句，即一方面
t1.table_1_team IN ('team1', 'team2', 'team3') AND
t1.table_1_id NOT IN (1,3,6,8,10);
和另一个
t1.table_1_id IN (1,3,6,8,10)
有人可以帮我吗？
答案 0 :(得分：0)
我认为这就是您想要的。 至少至少可以简化您的查询。
SELECT
t1.table_1_id AS t1_id，t1.table_1_name AS t1_name，t1.table_1_team AS t1team
，t2.table_2_id AS t2_id，t2.table_2_name AS t2_name
，t4.table_4_id AS t4_id，t4.table_4_name AS t4_name
从table_1 t1
左联接table_2 t2 ON t2.table_1_id = t1.table_1_id
LEFT JOIN table_4 t4 ON EXISTS（-将联结表保留在主查询之外
选择1
从table_3 t3
在哪里t3.table_1_id = t1.table_1_id
AND t3.table_4_id = t4.table_4_id
）
在1 = 1
AND t1.table_1_team IN（'team1'，'team2'，'team3'）
-AND t1.table_1_id IN（1、3、6、8、10）
-至少两个左联接之一必须具有匹配的行。
-或t2.table_2_id不为空或t4.table_4_id不为空
依次订购1,4,6
;