第一次看到这样的SQL语句,看不懂,其中用到了下面的不常用的
聚集函数:GROUPING
用于汇总数据用的运算符: ROLLUP
SELECT CASE GROUPING(o.customerid) WHEN 0 THEN o.customerid ELSE ‘(Total)’ END AS AllCustomersSummary, CASE GROUPING(od.orderid) WHEN 0 THEN od.orderid ELSE -1 END AS IndividualCustomerSummary, SUM(od.quantity*od.unitprice) AS pric
