how can get with multipule columns with group by in sql server - sql

Question

Please need help if possible.
select a.* from (
select u.user_guid,u.user_name,u.user_email,u.user_type,
uinf.user_info_fname,uinf.user_info_lname,uinf.user_info_address,img.image_type,img.image_location,
v.visitor_datetime,v.visitor_duration,v.visitor_ip,v.media_guid
from
tb_visitors_log as v
left outer join tb_media as m on v.media_guid=m.media_guid left outer join
tb_users as u on v.user_guid=u.user_guid left outer join
tb_user_info as uinf on uinf.user_guid=u.user_guid
left outer join tb_images as img on img.image_guid=uinf.user_info_thumbnail
where v.media_guid=#media_guid and uinf.user_info_lname like concat('%',#searchvalue,'%')) as a
order by a.visitor_datetime desc
I want the output to be grouped by a.user_guid. In MySQL I do this:
select a.* from (select u.user_guid,u.user_name,u.user_email,u.user_type,
uinf.user_info_fname,uinf.user_info_lname,uinf.user_info_address,img.image_type,img.image_location,
v.visitor_datetime,v.visitor_duration,v.visitor_ip,v.media_guid
from
tb_visitors_log as v
left outer join tb_media as m on v.media_guid=m.media_guid left outer join
tb_users as u on v.user_guid=u.user_guid left outer join
tb_user_info as uinf on uinf.user_guid=u.user_guid
left outer join tb_images as img on img.image_guid=uinf.user_info_thumbnail
where v.media_guid=P_media_guid and uinf.user_info_lname like concat('%',P_searchvalue,'%')
order by v.visitor_datetime desc
) as a group by a.user_guid;
But in SQL Server 2012 I can't do that.
this my resultt https://plus.google.com/u/1/photos/104984108592274133808/albums/6044709663274953441/6044709665297999426?pid=6044709665297999426&oid=104984108592274133808
and this is the one i want to have https://plus.google.com/u/1/photos/104984108592274133808/albums/6044709663274953441/6044709666972693378?pid=6044709666972693378&oid=104984108592274133808

Answer 1

I see this kind of misconception about GROUP BY very often (damn you, MySQL!).
You cannot output columns directly, unless they are in your GROUP BY clause, or unless you have some aggregate function on them. Simple example. Suppose your base table looks like this:
+--------+----------+-------+
| UserId | UserName | Value |
+--------+----------+-------+
| 1 | Alpha | 150 |
| 1 | Alpha | 110 |
| 1 | Alpha | 170 |
| 2 | Bravo | 240 |
| 3 | Charlie | 350 |
| 3 | Charlie | 330 |
+--------+----------+-------+
Now say you only want one row for each user. You would then try something like this:
SELECT * FROM MyTable GROUP BY UserId
This will not work, because the database doesn't know what to do with the 2 columns that you didn't group upon. Now, some database engines (MySQL, grrr!) lets you do this anyway, and for the UserName column, this would probably be fine, since there seems to be a 1:1 relation between UserId and UserName. But for each user, you need to decide what to do with the Value column, since it seems to contain different values for the same UserId (here, MySQL would just pick a random value).
This is where you need to specify an aggregate function, such as SUM(), MAX(), MIN(), etc... So say you just want the maximum value for each user, you would have to do this:
SELECT UserId, UserName, MAX(Value) AS [MaximumValue]
FROM MyTable
GROUP BY UserId, UserName
Note here, that I had to GROUP BY both the UserId and UserName columns - this is because the database engine does not know about the 1:1 relation between these columns. Each time you find yourself listing a lot of columns from the same table in the GROUP BY part of your query, it typically indicates bad data design, which is the case in my sample table, since the UserName-column contains redundant data.

Answer 2

This i my answer if any one cares
select distinct u.user_guid,u.user_name,u.user_email,u.user_type,
uinf.user_info_fname,uinf.user_info_lname,uinf.user_info_address,img.image_type,img.image_location,
v.visitor_datetime,v.visitor_duration,v.visitor_ip,v.media_guid
from tb_visitors_log as v
left outer join tb_media as m on v.media_guid=m.media_guid left outer join
tb_users as u on v.user_guid=u.user_guid left outer join
tb_user_info as uinf on uinf.user_guid=u.user_guid
left outer join tb_images as img on img.image_guid=uinf.user_info_thumbnail
where u.user_guid in(
select distinct u.user_guid
from
tb_visitors_log as v
left outer join tb_media as m on v.media_guid=m.media_guid left outer join
tb_users as u on v.user_guid=u.user_guid left outer join
tb_user_info as uinf on uinf.user_guid=u.user_guid
left outer join tb_images as img on img.image_guid=uinf.user_info_thumbnail
where uinf.user_info_fname like concat('%',#searchvalue,'%') and v.media_guid=#media_guid)
and v.visitor_datetime in
(select max(v.visitor_datetime) from tb_visitors_log as v
left outer join tb_media as m on v.media_guid=m.media_guid left outer join
tb_users as u on v.user_guid=u.user_guid left outer join
tb_user_info as uinf on uinf.user_guid=u.user_guid
left outer join tb_images as img on img.image_guid=uinf.user_info_thumbnail
where v.media_guid=#media_guid and uinf.user_info_fname like concat('%',#searchvalue,'%') group by v.user_guid)
and v.media_guid=#media_guid