Function stitching recordset A field, comma separated

Data sheet: User

Id	Name	group_id
1	Tom	1
2	John doe	1
3	Harry	2

1. mysql, sqlite:group_contact function:

Select  from User Group  by group_id

Results:

Ids	group_id
The	1
3	2

2.mssql:stuff function + for XML PATH

Select Stuff((Select ','+Convert(varchar( -), id) from User  asT2whereT2.id=T1.id forXML PATH ("')),1,1,"') asids,group_id from User  asT1Group  bygroup_id

Results:

Ids	group_id
The	1
3	2

Function stitching recordset A field, comma separated