--320, SQL SERVER 日报
--查询2009-01-01当天客户A1,A2,A3的订单数量
SELECT Cust_Name
  , CONVERT(CHAR(10), Order_Date, 120) Order_Date
  , SUM(Qty) Qty
FROM Orders_Big
WHERE 1=1
  AND Cust_Name IN ('A1', 'A2', 'A3')
  AND Order_Date >= '2009-01-01'
  AND Order_Date<'2009-01-02'
  /*AND Order_Date -- BETWEEN...AND相当于>=和<=
   BETWEEN '2009-01-01'
     AND '2009-01-02'*/
GROUP BY Cust_Name
  , CONVERT(CHAR(10), Order_Date, 120)
ORDER BY 2, 1
--321. ORACLE 日报
--查询2009-01-01当天客户A1,A2,A3的订单数量
SELECT Cust_Name
 , TO_CHAR(Order_Date, 'YYYY-MM-DD') Order_Date --方法一:转换成字符串类型
 --, TRUNC(Order_Date) Order_Date --方法二:将时分秒信息截断
 , SUM(Qty) Qty
FROM Orders_Big
WHERE 1=1
  AND Cust_Name IN ('A1', 'A2', 'A3')
  AND Order_Date >= DATE'2009-01-01'
  AND Order_Date<DATE'2009-01-02'
GROUP BY Cust_Name
  , TO_CHAR(Order_Date, 'YYYY-MM-DD')--方法一
  --, TRUNC(Order_Date)--方法二
ORDER BY 2, 1
------------------------------10.2------------------------------------
--326,SQL SERVER 月报
SELECT Cust_Name
  , CONVERT(CHAR(7), Order_Date, 120) Order_YrMs
  , CAST(CONVERT(CHAR(7), Order_Date, 120) + '-01' AS DATETIME) Order_Date
  , SUM(Qty) Qty
FROM Orders_Big
WHERE 1=1
 AND Cust_Name IN ('A1', 'A2', 'A3')
 AND Order_Date >= '2009-01-01'
 AND Order_Date<'2009-02-01'
GROUP BY Cust_Name
  , CONVERT(CHAR(7), Order_Date, 120)
ORDER BY 2, 1
--326, ORACLE
SELECT Cust_Name
 , TO_CHAR(Order_Date, 'YYYY-MM') Order_YrMs --方法1
 --, TRUNC(Order_Date, 'MM') Order_Date--方法2
 , SUM(Qty) Qty
FROM Orders_Big
WHERE 1=1
 AND Cust_Name IN ('A1', 'A2', 'A3')
 AND Order_Date >= DATE'2009-01-01'
 AND Order_Date<DATE'2009-02-01'
GROUP BY Cust_Name
 , TO_CHAR(Order_Date, 'YYYY-MM')--方法1
 --, TRUNC(Order_Date, 'MM')--方法2
ORDER BY 2, 1