Question

我遇到Informix SQL语法问题。

这是我的SQL语法

sql = "SELECT MONTH(startdatetime) MONTH, COUNT(sessionid) TotalCallsOffered, "+

      " CASE" +
      " WHEN MONTH(startdatetime) = 5" +
      " THEN 'SUSUKUDA' " +
      " END " +

      "FROM agentconnectiondetail a WHERE MONTH(startdatetime) = 5 " +
      "GROUP BY 1 ORDER BY 1 ASC";

，输出

ERROR [HY000] [Informix][Informix ODBC Driver][Informix] The column ((expression))
must be in the GROUP BY list.

我该怎么办？

Answer 1

Informix遵循严格的SQL标准，并要求选择列表中的所有非聚合值都列在GROUP BY子句中。因此，SQL必须如下所示：

SELECT MONTH(startdatetime) AS Month, COUNT(sessionid) AS TotalCallsOffered,
       CASE
       WHEN MONTH(startdatetime) = 5
       THEN 'SUSUKUDA'
       END AS Susukuda
  FROM agentconnectiondetail
 WHERE MONTH(startdatetime) = 5
 GROUP BY Month, Susukuda
 ORDER BY Month ASC

我选择使用AS命名所有三列，并选择GROUP BY这些名称（以及ORDER BY）。

Answer 2

我的问题解决了这个

SELECT MONTH(startdatetime) AS Month, COUNT(sessionid) AS TotalCallsOffered,
       CASE
       WHEN MONTH(startdatetime) = 5
       THEN 'SUSUKUDA'
       END AS Susukuda
  FROM agentconnectiondetail
 WHERE MONTH(startdatetime) = 5
 GROUP BY 1, 3
 ORDER BY 1

Informix SQL - CASE语句中的错误

2 个答案: