四、排序查询:
1、语法:
SELECT <*|列名1,列名2 ...> FROM <表名> [WHERE条件]
[GROUP BY 分组列名...] [HAVING 分组后过滤条件]
[ORDER BY <列名1> 升序|降序...]
2、排序方式:
A、ASC 升序,为默认值
B、DESC 降序
3、例:
1)查询MyServer数据库产品列表ProductList 所有字段,按库存量升序排列
USE MyServer
GO
SELECT * FROM ProductList ORDER BY PL_Amount --未指定排序方式,默认为升序
GO
2)查询MyServer数据库产品列表ProductList 库存量大于记录,并按库存量降序排列
USE MyServer
GO
SELECT * FROM ProductList
WHERE PL_Amount>
ORDER BY PL_Amount DESC
GO
3)查询MyServer数据库产品列表ProductList,按产品类别名称(字段名:P_Id)1、3来求和库存量且需大于的记录,并按升序排列
USE MyServer
GO
SELECT P_Id,sum(PL_Amount) FROM ProductList
WHERE P_Id=1 OR P_Id=3
GROUP BY P_Id
HAVING SUM(PL_Amount)>
ORDER BY sum(PL_Amount) ASC
GO
4、TQL语句(即查询)执行顺序说明: