Several simple queries of SQL Server database

In the case of a large number of database files , To find a piece of information more clearly and quickly , Here are some examples 3 Kind of SQL Query methods ：

1、 Projection query

2、 Select query

3、 Sort query

The following is the database table for testing Table:

The first is projection query , In order to make the viewed data more explicit , Understandability .

There are three ways to write projection queries ：

① select CID Customer number ,CContact Contacts ,CPhone contact number ,CIntegration integral from Table

② select CID AS Customer number ,CContact AS Contacts ,CPhone AS contact number ,CIntegration AS integral from Table

③ select Customer number =CID, Contacts =CContact, contact number =CPhone, integral =CIntegration from Table

Projection query result ：

Secondly, select query , In order to accurately find the data content of the condition .

select * from Table where CIntegration<=24 and CPhone like '%244575%'

% Represents a string of arbitrary length

Select query score less than 24 And the phone number is 244575 The data result of ：

Finally, the sorting query , In ascending and descending order .

select * from Table order by CIntegration desc

desc： Descending ,asc： Ascending , The default is ascending

Sort query results ：

This is it. SQL Server Database 3 A simple query method .