列'Buy.title'在选择列表中无效，因为它不包含在聚合函数或GROUP BY子句中

Question

IF(@sal IS NOT NULL AND @title IS NOT NULL)
BEGIN
    SELECT title,type1, SUM(tedat) FROM Buy
    WHERE(@sal = YEAR(tarikh) AND @title = title)

END

Answer 1

您必须对结果集上不在聚合函数内的列进行分组。因此，它将对具有相同标题和类型的记录组应用聚合函数（求和）。

文档：SQL Server GROUP BY clause

IF(@sal IS NOT NULL AND @title IS NOT NULL)
BEGIN
    SELECT title,type1, SUM(tedat) 
    FROM Buy
    WHERE(@sal = YEAR(tarikh) AND @title = title)
    GROUP BY title, type1
END