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Legal Studies在 UPDATE 查詢的 SET 部分中反引號不起作用（對於 MySQL）的原因是什麼？
反引號在以下語法中正確編寫時可以工作 −
update `yourTableName` set `yourTableName`.`yourColumnName`='yourNewValue' where yourCondition;
我們先建立一個 −
mysql> create table `DemoTable_1401` -> ( -> Name varchar(20) -> ); Query OK, 0 rows affected (0.52 sec)
使用 insert 在表中插入一些記錄 −
mysql> insert into `DemoTable_1401` values('Chris');
Query OK, 1 row affected (0.16 sec)
mysql> insert into `DemoTable_1401` values('David');
Query OK, 1 row affected (0.10 sec)
mysql> insert into `DemoTable_1401` values('Bob');
Query OK, 1 row affected (0.12 sec)使用 select 從表中顯示所有記錄 −
mysql> select * from `DemoTable_1401`;
這將產生以下輸出 −
+-------+ | Name | +-------+ | Chris | | David | | Bob | +-------+ 3 rows in set (0.00 sec)
以下是對反引號起作用的查詢 −
mysql> update `DemoTable_1401` set `DemoTable_1401`.`Name`='Adam' where `Name`='David'; Query OK, 1 row affected (0.15 sec) Rows matched: 1 Changed: 1 Warnings: 0
讓我們再次檢查表記錄 −
mysql> select * from `DemoTable_1401`;
這將產生以下輸出 −
+-------+ | Name | +-------+ | Chris | | Adam | | Bob | +-------+ 3 rows in set (0.00 sec)
更新於： 11-11-2019
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