MySQL中的CONCAT（）

Question

我需要像SELECT CONCAT(SUM(transactioninfo.CreditAmount),'Cr') AS creditdAmount FROM transaction; 这样的输出，我试过这个：

500000

但我只获得Id CreditAmount DebitAmount Transactiondate -- ------------ ----------- --------------- 1 100000 0 2015-12-08 2 100000 5000 2015-12-08 3 100000 2000 2015-12-08 4 100000 3000 2015-12-08 5 100000 5000 2015-12-08 。

表格结构：

ActiveRecord

Answer 1

请检查以下内容。这对你来说是值得的：

SELECT 
CONCAT(CONVERT(SUM(transactioninfo.CreditAmount), char), ' (Cr)') AS creditdAmount 
FROM transactioninfo

Answer 2

您可以尝试将您的值作为varchar进行CAST，然后尝试这样：

SELECT  CONCAT(CAST(SUM(transactioninfo.CreditAmount) AS char(20)),' (Cr)') AS creditdAmount FROM transactioninfo;

Answer 3

您可以使用此查询

 SELECT concat(creditdAmount,' (Cr)') FROM  
   (  
    SELECT SUM(id) AS creditdAmount FROM transaction  
   )as temp;