如何在我的情況下使用內部聯接

Question

我有兩個這樣的桌子

   c_ID    name
    ---   ------
    7      a
    6      a
    5      a
    4      d

和

   c_ID    photo
  -----   ------
    7       1
    6       1
    5       0
    4       1

如何選擇名稱為a且照片為1 ？

謝謝

Answer 1

select *  /*TODO: Add specific column(s) you want here*/
from   table1
       join table2
         on table1.c_ID = table2.c_ID
where  table1.name = 'a'
       and table2.photo = 1  

Answer 2

SELECT * 
FROM table1 AS name LEFT JOIN table2 AS photo ON name.c_ID = photo.c_ID 
WHERE name.name = 'a' and photo.photo = 1

話雖這么說，您的示例看起來可能可以將兩個表歸一化為一個包含c_ID，名稱和照片字段的表

Answer 3

嘗試這個：

SELECT table1.c_id, table1.name, table2.photo
  FROM table1 INNER JOIN table2
 ON table1.c_id = table2.c_id
   AND table1.name = 'a'
   AND table2.photo = 1

Answer 4

SELECT t1.*, t2.*
FROM table1 t1
JOIN table2 t2 ON t2.c_ID = t1.c_ID
WHERE t1.name = 'a' AND t2.photo = 1

最好不要在數據庫中使用大寫字符。

Answer 5

SELECT table1.c_ID, table1.name, table2.photo              // desired fields
FROM table1 INNER JOIN table2 ON table1.c_ID=table2.c_ID   // joining tables on common keys
WHERE table1.name='a' AND table2.photo=1;                  // desired condition