从一个表中查找另一个表中不存在的记录

我有以下两个表(在MySQL):

Phone_book
+----+------+--------------+
| id | name | phone_number |
+----+------+--------------+
| 1  | John | 111111111111 |
+----+------+--------------+
| 2  | Jane | 222222222222 |
+----+------+--------------+

Call
+----+------+--------------+
| id | date | phone_number |
+----+------+--------------+
| 1  | 0945 | 111111111111 |
+----+------+--------------+
| 2  | 0950 | 222222222222 |
+----+------+--------------+
| 3  | 1045 | 333333333333 |
+----+------+--------------+

我如何找出哪些电话是由电话号码不在电话簿中的人打的?期望的输出将是:

Call
+----+------+--------------+
| id | date | phone_number |
+----+------+--------------+
| 3  | 1045 | 333333333333 |
+----+------+--------------+

当前回答

我认为

SELECT CALL.* FROM CALL LEFT JOIN Phone_book ON 
CALL.id = Phone_book.id WHERE Phone_book.name IS NULL

2012-02-15 12:39:13

其他回答

SELECT t1.ColumnID,
CASE 
    WHEN NOT EXISTS( SELECT t2.FieldText  
                     FROM Table t2 
                     WHERE t2.ColumnID = t1.ColumnID) 
    THEN t1.FieldText
    ELSE t2.FieldText
END FieldText       
FROM Table1 t1, Table2 t2

2013-10-24 14:53:22

另外,

select id from call
minus
select id from phone_number

2017-08-21 11:55:32

我认为

SELECT CALL.* FROM CALL LEFT JOIN Phone_book ON 
CALL.id = Phone_book.id WHERE Phone_book.name IS NULL

2012-02-15 12:39:13

SELECT Call.ID, Call.date, Call.phone_number 
FROM Call 
LEFT OUTER JOIN Phone_Book 
  ON (Call.phone_number=Phone_book.phone_number) 
  WHERE Phone_book.phone_number IS NULL

应该删除子查询，允许查询优化器发挥它的魔力。

另外，避免使用“SELECT *”，因为如果有人更改了底层表或视图，它会破坏代码(而且效率很低)。

2008-12-15 11:51:40

SELECT DISTINCT Call.id 
FROM Call 
LEFT OUTER JOIN Phone_book USING (id) 
WHERE Phone_book.id IS NULL

这将返回Phone_book表中缺少的额外id。

2013-01-16 10:42:29

从一个表中查找另一个表中不存在的记录

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