Doctrine 2 DQL CONCAT字段和常量字符串

Question

我有字段firstname和lastname我的MySQL表.为方便起见,我想在我的Doctrine 2实体中添加一个计算列full_name.在普通的MySQL中我会做这样的事情

SELECT CONCAT(firstname, " ", lastname) AS full_name FROM customers;

但是,连接字段和常量字符串(在这种情况下为"")似乎不适用于Doctrine的CONCAT实现.使用以下代码时

$repository
    ->createQueryBuilder('customer')
    ->select('CONCAT(customer.firstname, " ", customer.lastname) AS full_name')
    // ...

我收到了错误

[Syntax Error] line 0, col 91: Error: Expected StateFieldPathExpression | string | InputParameter | FunctionsReturningStrings | AggregateExpression, got '"'

我怎样才能实现与MySQL相同的行为？

Answer 1

显然,DQL中的字符串只能用单引号封装,而不能用双引号封装.文档中的简短搜索并未直接提及此行为,但我注意到所有包含常量字符串的示例都使用单引号.

更改

->select('CONCAT(customer.firstname, " ", customer.lastname) AS full_name')

至

->select('CONCAT(customer.firstname, \' \', customer.lastname) AS full_name')

要么

->select("CONCAT(customer.firstname, ' ', customer.lastname) AS full_name")

解决了这个问题