[SQL ] 算UNION後的個數

[kalecgos0616 (.)]

資料庫是MySQL 5.0.77

我現在有兩個資料表:
table1:
Id      店面
Tom       A
Tom       B
代表Tom有A, B店面

table2:
店面    倉庫
A       C
A       D
A       E
B       C
B       D
B       E
代表A店面有C, D倉庫; B店面有E倉庫

現在透過UNION已經能能顯示出下面這樣的結果:
Id      地點
Tom       A
Tom       B
Tom       C
Tom       D
Tom       E
代表Tom擁有以下地點

我用這句sql:
SELECT a.ActorId, a.LocationId
FROM `Jurisdiction` AS a
WHERE ActorId =Tom
UNION SELECT a.ActorId, b.WarehouseId AS LocationId
FROM `Jurisdiction` AS a, `LocationRelationship` AS b
WHERE a.LocationId = b.ShopId
AND a.ActorId =Tom

我現在想算這個select的個數
使用這句sql:
SELECT ((SELECT COUNT(*)
FROM `Jurisdiction` AS a
WHERE ActorId =Tom)
+ (SELECT COUNT(*)
FROM `Jurisdiction` AS a, `LocationRelationship` AS b
WHERE a.LocationId = b.ShopId
AND a.ActorId =Tom))AS total

算出total是8與結果不合

後來發現前面那句sql的total是2後面那句sql的total是6

將後面那句sql多select幾個欄位後 select出來是
ActorId         ShopId          WarehouseId
Tom             A               C
Tom             A               D
Tom             A               E
Tom             B               C
Tom             B               D
Tom             B               E

要怎麼樣select出這樣，重複的WarehouseId就不顯示呢？
ActorId         ShopId          LocationId
Tom             A               C
Tom             A               D
Tom             A               E

--
※ 發信站: 批踢踢實業坊(ptt.cc) 
◆ From: 59.125.41.241
→ grence:"代表A店面有C, D倉庫;"←敘述跟例子不符，還是我誤解 囧a
→ kalecgos0616:自問自答，後面那句用DISTINCT 就可以了