在SQL中合并行中的相似ID？

Question

我现在有一个有趣的困境。我有一个数据库架构如下所示：

GameList: 
+-------+----------+-----------+------------+--------------------------------+ 
| id | steam_id | origin_id | impulse_id |   game_title   | 
+-------+----------+-----------+------------+--------------------------------+ 
| 1 | 17450 | NULL | NULL |  Dragon Age: Origins  | 
| 2 | NULL | 138994900 | NULL | Dragon Age(TM): Origins  | 
| 3 | NULL | NULL | dragonage |  Dragon Age Origins  | 
| 4 | 47850 | 201841300 | fifamgr11 |  FIFA Manager 11   | 
| ... | ... | ... |  ... |    ...    | 
+-------+----------+-----------+------------+--------------------------------+ 

GameAlias: 
+----------+-----------+ 
| old_id | new_id | 
+----------+-----------+ 
| 2  |  1  | 
| 3  |  1  | 
| ... | ... | 
+----------+-----------+ 

根据门店是否使用游戏相同的标题有可能是没有问题的，或者同一游戏可以有多个行。别名表存在解决此问题，通过说明id 2和id 3只是id 1的别名。

我需要的是一个SQL查询，它同时使用GameList表和GameAlias表并返回以下内容：

ConglomerateGameList: 
+-------+----------+-----------+------------+--------------------------------+ 
| id | steam_id | origin_id | impulse_id |   game_title   | 
+-------+----------+-----------+------------+--------------------------------+ 
| 1 | 17450 | 138994900 | dragonage |  Dragon Age: Origins  | 
| 4 | 47850 | 201841300 | fifamgr11 |  FIFA Manager 11   | 
| ... | ... | ... |  ... |    ...    | 
+-------+----------+-----------+------------+--------------------------------+ 

请注意，我想要“新身份证”的游戏标题。任何“老ids”的游戏标题都应该简单地放弃/忽略。

我也想指出，我不能做任何修改的游戏列表表来解决这个问题。如果我只是重新写表每天晚上看起来像我那么所需的输出，当我抓住从它会无法在数据库中找到游戏中的商店的更新游戏列表，产生又喜欢另一行这样：

+-------+----------+-----------+------------+--------------------------------+ 
| id | steam_id | origin_id | impulse_id |   game_title   | 
+-------+----------+-----------+------------+--------------------------------+ 
| 1 | 17450 | 138994900 | dragonage |  Dragon Age: Origins  | 
| 4 | 47850 | 201841300 | fifamgr11 |  FIFA Manager 11   | 
| ... | ... | ... |  ... |    ...    | 
| 8139 | NULL | 138994900 | NULL |  Dragon Age(TM): Origins | 
| 8140 | NULL | NULL | dragonage |  Dragon Age Origins  | 
+-------+----------+-----------+------------+--------------------------------+ 

我也不能假设的工作，如蒸汽已经知道，改变他们被释放到游戏中的重大更新，当一个游戏的ID将永远不会改变。如果

奖励积分它可以识别递归的别名，如下所示：

GameAlias: 
+----------+-----------+ 
| old_id | new_id | 
+----------+-----------+ 
| 2  |  1  | 
| 3  |  2  | 
| ... | ... | 
+----------+-----------+ 

由于ID 3是用于ID 2的别名，其本身是用于ID 1的别名如果递归别名是不可能的话，我可以只是开发我的应用程序逻辑来防止它们。

Answer 1

工作的呢？纠正表名。

select ga1.new_id, max(gl1.steam_id), max(gl1.origin_id), max(gl1.impulse_id), 
max(if(gl1.id = ga1.new_id,gl1.game_title,NULL)) as game_title 
from gl1, ga1 
where (gl1.id = ga1.new_id OR gl1.id = ga1.old_id) 
group by ga1.new_id 

union 

select gl2.id, gl2.steam_id, gl2.origin_id, gl2.impulse_id, gl2.game_title 
from gl2, ga2 
where (gl2.id not in (
    select ga3.new_id from ga3 
    union 
    select ga4.old_id from ga4)) 

Answer 2

1。第一溶液（无递归）：

CREATE TABLE GameList 
(
    id   INT NOT NULL PRIMARY KEY 
    ,steam_id INT NULL 
    ,origin_id INT NULL 
    ,impulse_id NVARCHAR(50) NULL    
    ,game_title NVARCHAR(50) NOT NULL 
); 
INSERT GameList(id, steam_id, origin_id, impulse_id, game_title) 
SELECT 1, 17450, NULL,  NULL,  'Dragon Age: Origins' 
UNION ALL 
SELECT 2, NULL, 138994900, NULL,  'Dragon Age(TM): Origins' 
UNION ALL 
SELECT 3, NULL, NULL,  'dragonage','Dragon Age Origins' 
UNION ALL 
SELECT 4, 47850, 201841300, 'fifamgr11','FIFA Manager 11'; 

CREATE TABLE GameAlias 
(
    old_id INT NOT NULL PRIMARY KEY 
    ,new_id INT NOT NULL 
); 

INSERT GameAlias (old_id, new_id) VALUES (2,1); 
INSERT GameAlias (old_id, new_id) VALUES (3,1); 

-- Solution 1 
SELECT COALESCE(ga.new_id, gl.id) new_id 
     ,MAX(gl.steam_id) new_steam_id 
     ,MAX(gl.origin_id) new_origin_id 
     ,MAX(gl.impulse_id) new_impulse_id 
     ,MAX(CASE WHEN ga.old_id IS NULL THEN gl.game_title ELSE NULL END) new_game_title 
FROM GameList gl 
LEFT OUTER JOIN GameAlias ga ON gl.id = ga.old_id 
GROUP BY COALESCE(ga.new_id, gl.id); 
-- End of Solution 1  
DROP TABLE GameList; 
DROP TABLE GameAlias; 

结果：

1 17450 138994900 dragonage Dragon Age: Origins 
4 47850 201841300 fifamgr11 FIFA Manager 11 

2.Second溶液（递归级别=三级）：

CREATE TABLE GameList 
(
    id   INT NOT NULL PRIMARY KEY 
    ,steam_id INT NULL 
    ,origin_id INT NULL 
    ,impulse_id NVARCHAR(50) NULL    
    ,game_title NVARCHAR(50) NOT NULL 
); 
INSERT GameList(id, steam_id, origin_id, impulse_id, game_title) 
SELECT 1, 17450, NULL,  NULL,  'Dragon Age: Origins' 
UNION ALL 
SELECT 2, NULL, 138994900, NULL,  'Dragon Age(TM): Origins' 
UNION ALL 
SELECT 3, NULL, NULL,  'dragonage','Dragon Age Origins' 
UNION ALL 
SELECT 4, 47850, 201841300, 'fifamgr11','FIFA Manager 11' 
UNION ALL 
SELECT 5, 11111, NULL,  NULL,  'Starcraft 1' 
UNION ALL 
SELECT 6, NULL, 1111111111, NULL,  'Starcraft 1.1' 
UNION ALL 
SELECT 7, NULL, NULL,  NULL,  'Starcraft 1.2' 
UNION ALL 
SELECT 8, NULL, NULL,  'sc1',  'Starcraft 1.3'; 

CREATE TABLE GameAlias 
(
    old_id INT NOT NULL PRIMARY KEY 
    ,new_id INT NOT NULL 
); 

INSERT GameAlias (old_id, new_id) VALUES (2,1); 
INSERT GameAlias (old_id, new_id) VALUES (3,1); 
INSERT GameAlias (old_id, new_id) VALUES (6,5); 
INSERT GameAlias (old_id, new_id) VALUES (7,6); 
INSERT GameAlias (old_id, new_id) VALUES (8,7); 

-- Solution 2 
CREATE TEMPORARY TABLE Mappings 
(
    old_id INT NOT NULL PRIMARY KEY 
    ,new_id INT NOT NULL 
); 
INSERT Mappings (old_id, new_id) 
-- first level mapping 
SELECT ga.old_id, ga.new_id 
FROM GameAlias ga 
WHERE ga.new_id NOT IN (SELECT t.old_id FROM GameAlias t) 
-- second level mapping 
UNION ALL 
SELECT ga.old_id, ga2.new_id 
FROM GameAlias ga 
INNER JOIN GameAlias ga2 ON ga.new_id = ga2.old_id 
WHERE ga2.new_id NOT IN (SELECT t.old_id FROM GameAlias t) 
-- third level mapping 
UNION ALL 
SELECT ga.old_id, ga3.new_id 
FROM GameAlias ga 
INNER JOIN GameAlias ga2 ON ga.new_id = ga2.old_id 
INNER JOIN GameAlias ga3 ON ga2.new_id = ga3.old_id; 

SELECT COALESCE(ga.new_id, gl.id) new_id 
     ,MAX(gl.steam_id) new_steam_id 
     ,MAX(gl.origin_id) new_origin_id 
     ,MAX(gl.impulse_id) new_impulse_id 
     ,MAX(CASE WHEN ga.old_id IS NULL THEN gl.game_title ELSE NULL END) new_game_title 
FROM GameList gl 
LEFT OUTER JOIN Mappings ga ON gl.id = ga.old_id 
GROUP BY COALESCE(ga.new_id, gl.id); 

DROP TEMPORARY TABLE Mappings; 
-- End of Solution 2 

DROP TABLE GameList; 
DROP TABLE GameAlias; 

结果：

1 17450 138994900 dragonage Dragon Age: Origins 
4 47850 201841300 fifamgr11 FIFA Manager 11 
5 11111 1111111111 sc1   Starcraft 1 

对不起，但MySQL没有递归查询/ CTE。