Question

这是有效的查询

UPDATE 18_6_TransactionPartners SET CompanyName = ?, VatCode = ? 
WHERE CompanyName = ? OR RegistrationNumber = ?

我只想在一个查询中进行多次更新，例如

UPDATE 18_6_TransactionPartners SET CompanyName = ?, VatCode = ? 
WHERE CompanyName = ? OR RegistrationNumber = ?

UPDATE 18_6_TransactionPartners SET CompanyName = ?, VatCode = ? 
WHERE CompanyName = ? OR RegistrationNumber = ?

基于此http://blog.bubble.ro/how-to-make-multiple-updates-using-a-single-query-in-mysql/示例

UPDATE mytable
SET (title='Great Expectations' WHERE id='1'),
(title='War and Peace' WHERE id='2');

将查询更改为此

UPDATE 18_6_TransactionPartners 
SET (CompanyName = ?, VatCode = ? WHERE CompanyName = ? OR RegistrationNumber = ?), 
(CompanyName = ?, VatCode = ? WHERE CompanyName = ? OR RegistrationNumber = ?)

但是得到错误Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '(CompanyName = 'first name', VatCode = '123' WHERE CompanyName = 'first name' OR'

据了解，错误发生在SET之后。

删除了括号。首先CompanyName = ?, VatCode = ? WHERE CompanyName = ? OR RegistrationNumber = ?没有错误，但错误接近第二CompanyName = ?, VatCode = ?

什么是正确的语法？

也尝试了这个https://stackoverflow.com/a/15344247/2465936

UPDATE 18_6_TransactionPartners 
SET value = CASE 
WHEN CompanyName = ? OR RegistrationNumber = ? THEN CompanyName = ?, VatCode = ? , 
WHEN CompanyName = ? OR RegistrationNumber = ? THEN CompanyName = ?, VatCode = ? 
ELSE CompanyName, RegistrationNumber END

但是得到错误SQLSTATE[42000]: Syntax error or access violation: 1064 You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ' VatCode = '123' , WHEN CompanyName = 'second name' OR RegistrationNumber = 'ttt'

更新

实验并运行此类代码：

UPDATE 18_6_TransactionPartners SET RegistrationNumber = (
CASE
WHEN CompanyName = 1 OR VatCode = 1 THEN 1
WHEN CompanyName = 2 OR VatCode = 2 THEN 2
WHEN CompanyName = 3 OR VatCode = 'three' THEN 'three'
ELSE RegistrationNumber
END)
WHERE CompanyName IN ('1', '2', '3') OR VatCode IN ( 1, 2, 'three' ) //aim is to search table only where `WHERE` is true

因此，对于每个UPDATE只有一个SET RegistrationNumber = CASE，但可以设置多个条件WHEN CompanyName = 1 OR VatCode = 1。

接下来尝试合并多个UPDATE 18_6_TransactionPartners SET RegistrationNumber = CASE UPDATE 18_6_TransactionPartners SET RegistrationNumberNEXT = CASE

或需要创建多个查询....似乎需要尝试此示例http://code.openark.org/blog/mysql/multi-condition-update-query

UPDATE
 film
SET
 rental_duration=IF(rating = 'G', rental_duration+1, rental_duration),
 rental_rate=IF(length < 90, rental_rate-0.5, rental_rate)
WHERE
 rating = 'G'
 OR length < 90

Answer 1

不，这是不正确的，不起作用。正如manual所述，UPDATE具有以下语法：

UPDATE [LOW_PRIORITY] [IGNORE] table_reference
    SET col_name1={expr1|DEFAULT} [, col_name2={expr2|DEFAULT}] ...
    [WHERE where_condition]
    [ORDER BY ...]
    [LIMIT row_count]

请求中只能有1个WHERE子句。实际上，您的博客页面清楚地说：“您不能在单个UPDATE查询中对表进行多项更改，如此”。

他正在使用CASE命令：

UPDATE mytable SET title = CASE
    WHEN id = 1 THEN 'Great Expectations'
    WHEN id = 2 THEN 'War and Peace'
ELSE title
END;

但CASE仅适用于1个变量：

CASE case_value
    WHEN when_value THEN statement_list
    [WHEN when_value THEN statement_list] ...
    [ELSE statement_list]
END CASE

它不适用于像你这样的复合条款：

CompanyName = ? OR RegistrationNumber = ?

因此，您必须发送几个UPDATE请求。 EDIT 从CASE条件

中删除了半冒号

Answer 2

您需要CASE：

UPDATE mytable
SET title= (CASE WHEN id='1' THEN 'Great Expectations' ELSE 'War and Peace' END) 
WHERE id IN ('1','2');

带有多个WHERE的PHP MySQL更新（语法错误）

2 个答案: