SQL Server stuff and for XML path

Required press type After group query , Put the same type Of ,name Merge column values , Achieve the following results ：

The analysis is as follows ：

One 、FOR xml path

     FOR XML PATH Some may know, some may not know , Actually It is to query the result set with XML Formal display , With it, we can simplify our query statements and realize some work that may need to be completed with the help of functions or stored procedures . Let's take an example .

Suppose there is a query table as follows

sql  One ：

select type,name from tb_account where name like '% Test induction %' FOR xml path

Query results

<row> <type>0</type> <name> Test login </name> </row> <row> <type>1</type> <name> Test induction 6</name> </row> <row> <type>0</type> <name> Test induction </name> </row>

sql  Two ：

select type,name from tb_account where name like '% Test induction %' FOR xml path('')

 Query results ：
<type>0</type> <name> Test login </name> <type>1</type> <name> Test induction 6</name> <type>0</type> <name> Test induction </name>

sql  3、 ... and ：
select type,name from tb_account where name like '% Test induction %' FOR xml path('root') 
 Query results  ：
<root> <type>0</type> <name> Test login </name> </root> <root> <type>1</type> <name> Test induction 6</name> </root> <root> <type>0</type> <name> Test induction </name> </root>

sql  Four ：
select 10+type,','+name+',' from tb_account where name like '% Test induction %' FOR xml path('')
 Query results 
10, Test login ,11, Test induction 6,10, Test induction ,

  Two 、stuff function 
 stuff(param1, startIndex, length, param2)
 explain ： take param1 Zhongzi startIndex(SQL It's all from 1 Start , Instead of 0) rise , Delete length Characters , And then use param2 Replace deleted characters .
 remarks  
 If the start position or length value is negative , If the length of the string is greater than the first position , Will return an empty string . If the length to be deleted is greater than the length of the first string , Will delete the first character in the first string . 
 Example  
 The following example is in the first string  abcdef  Delete from section  2  A place （ character  b） The first three characters , Then insert a second string at the beginning of the deletion , To create and return a string .
SELECT STUFF('abcdef', 2, 3, 'ijklmn'); 
 GO
 Here's the result set ： 
 --------- 
 aijklmnef