SQL必知必会--检索数据

select：从一个表或者多个表中检索信息。

检索单个列：select prod_name from Products

检索多个列：select prod_name, prod_price,prod_id from Products

检索所有的列：select * from Products

注：* 是通配符

按单列排序：order by

select prod_name from Products order by prod_name

注：order by 一定是放在句子最后，其使用的列一般是检索列，但是是非检索列也可以。

按多列排序：select [vend_name],[vend_address]  FROM [Test].[dbo].[Vendors] order by vend_name , [vend_address]

按列位置排序： select [vend_name],[vend_address]  FROM [Test].[dbo].[Vendors] order by 1,2

注：2 是select清单中的第二列

指定排序方向：DESC降序

 select [vend_name],[vend_address] FROM [Test].[dbo].[Vendors] order by [vend_name], [vend_address] desc

注：默认是升序