如何在 MySQL 中刪除除部分行以外的所有行?
對於不想刪除的行,可以使用 NOT IN 運算子。以下是語法 −
delete from yourTableName where yourColumnName NOT IN(‘yourValue1’,‘yourValue2’,‘yourValue3’,.........N);
讓我們首先建立一個表 −
mysql> create table deleteAllRowsWithCondition -> ( -> Id int NOT NULL AUTO_INCREMENT PRIMARY KEY, -> Name varchar(20) -> ); Query OK, 0 rows affected (0.84 sec)
以下是使用 insert 命令向表中插入一些記錄的查詢 −
mysql> insert into deleteAllRowsWithCondition(Name) values('Larry'); Query OK, 1 row affected (0.14 sec) mysql> insert into deleteAllRowsWithCondition(Name) values('John'); Query OK, 1 row affected (0.21 sec) mysql> insert into deleteAllRowsWithCondition(Name) values('Sam'); Query OK, 1 row affected (0.12 sec) mysql> insert into deleteAllRowsWithCondition(Name) values('Mike'); Query OK, 1 row affected (0.16 sec) mysql> insert into deleteAllRowsWithCondition(Name) values('Carol'); Query OK, 1 row affected (0.14 sec) mysql> insert into deleteAllRowsWithCondition(Name) values('Bob'); Query OK, 1 row affected (0.06 sec) mysql> insert into deleteAllRowsWithCondition(Name) values('David'); Query OK, 1 row affected (0.14 sec)
以下是使用 select 語句顯示錶中所有記錄的查詢 −
mysql> select * from deleteAllRowsWithCondition;
這將產生以下輸出 −
+----+-------+ | Id | Name | +----+-------+ | 1 | Larry | | 2 | John | | 3 | Sam | | 4 | Mike | | 5 | Carol | | 6 | Bob | | 7 | David | +----+-------+ 7 rows in set (0.00 sec)
以下是刪除具有某些條件的所有行的查詢。我們在這裡不刪除“John”、“Mike”和“Carol” −
mysql> delete from deleteAllRowsWithCondition where Name NOT IN('John','Mike','Carol'); Query OK, 4 rows affected (0.15 sec)
讓我們檢查一下是否已從表中刪除某些行。以下是查詢 −
mysql> select * from deleteAllRowsWithCondition;
這將產生以下輸出 −
+----+-------+ | Id | Name | +----+-------+ | 2 | John | | 4 | Mike | | 5 | Carol | +----+-------+ 3 rows in set (0.00 sec)
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