GROUP BY query text columns - sql

Question

I'm using a query, I want to group them by 1 specific column. i get an error for other field witch are not listed in GROUP BY clause, yes i know i should tell Sql Server witch row of grouped by rows you should pick but i don't know how to do that. If that's int i use MIN() function and if its a text field i don't know what to do.
I want to select all data and if videos.number,videos.title is replicated than get the first row of grouped rows. What this query do is: get all channels from packages according to client subscription. sometime different packages have same channels and I don't want this channel to be shown twice to client.
USE [DB]
SELECT Videos.number,
Videos.title,
Videos.description,
Videos.format,
Videos.urlTwo AS url,
Videos.icon,
Videos.streamtype,
'pin' AS password,
Videos.categoryid,
Videos.videotype,
FROM subscription
INNER JOIN packages_channels
ON subscription.pkgid = packages_channels.package_id
INNER JOIN Videos
ON packages_channels.video_id = Videos.number
WHERE (GETDATE() >= subscription.startdate)
AND (GETDATE() <= subscription.enddate)
AND (subscription.username = 'mon1')
GROUP BY videos.number, Videos.title
ORDER BY Videos.number asc
this is what it shows right now:
number title description format url icon
101 channel1 101 101 URLstream1 iconPath1
101 channel1 101 101 URLstream1 iconPath1
102 channel2 101 102 URLstream2 iconPath2
107 channel7 107 107 URLstream7 iconPath7
108 channel8 108 108 URLstream8 iconPath8
but the result i want to get is this:
number title description format url icon
101 channel1 101 101 URLstream1 iconPath1
102 channel2 101 102 URLstream2 iconPath2
107 channel7 107 107 URLstream7 iconPath7
108 channel8 108 108 URLstream8 iconPath8
as you see channel1 its only once
url,and icon is the problem. this fields are text
I can't show a real sql result for security reason.

Answer 1

I don't think you really need a group by here since you are not using any aggregate function.
Using distinct will hopefully do the job like below
SELECT DISTINCT
Videos.number,
Videos.title,
Videos.description,
Videos.format,
convert(varchar(max),Videos.urlTwo) AS url,
convert(varchar(max),Videos.icon) as icon,
Videos.streamtype,
'pin' AS password,
Videos.categoryid,
Videos.videotype
FROM subscription
INNER JOIN packages_channels
ON subscription.pkgid = packages_channels.package_id
INNER JOIN Videos
ON packages_channels.video_id = Videos.number
WHERE (GETDATE() >= subscription.startdate)
AND (GETDATE() <= subscription.enddate)
AND (subscription.username = 'mon1')
ORDER BY Videos.number asc

Answer 2

If the other columns such as description and format are functionally dependant on the column you want to group on, you can simply include them in the group by clause.
Functional Dependancy means that the column will always have the same value for a certain value of the column it is functionally dependant on.
If they are not functionally dependant, then this simply will not work, because if you have different descriptions for one number, how is the SQL Server to determine which description to display?
One way to overcome this is by using MAX(Description) for instance. This makes an arbitrary choice for the description that happens to come last alphabetically.