sql查詢（輸出效果都沒有2個表之間的相同）

Question

我有2臺TableA和TableB與id, character

TableA 
╔════╦═══════════╗ 
║ id ║ character ║ 
╠════╬═══════════╣ 
║ 1 ║  A  ║ 
║ 2 ║  B  ║ 
║ 3 ║  C  ║ 
╚════╩═══════════╝ 

TableB 
╔════╦═══════════╗ 
║ id ║ character ║ 
╠════╬═══════════╣ 
║ 1 ║  A  ║ 
║ 2 ║  B  ║ 
║ 3 ║  D  ║ 
╚════╩═══════════╝ 

我要計算有多少個字符的字符列之間不匹配的屬性TableA和TableB。

我不知道這是否是正確的：

SELECT COUNT(character) 
FROM TableA tba 
JOIN TableB tbb 
    ON tba.id = tbb.id 
WHERE tba.character NOT LIKE tbb.character 
GROUP BY character 

Answer 1

你不聲明需要組：

SELECT COUNT(*) 
FROM TableA tba 
INNER JOIN TableB tbb 
    ON tba.id = tbb.id 
WHERE tba.character <> tbb.character