SQL计数列和列表值计数

Question

I am trying to create a query that will output a count of a column and then list the names it counted:

Table 1: license_granted

users      checkout  
Bob        2014-11-18 01:00:00  
Steve      2014-11-18 01:00:00
Bob        2014-11-18 01:30:00
Chris      2014-11-18 01:30:00

I am able to do my count and get this output:

checkout_time            ctUsers  
2014-11-18 01:00:00         2
2014-11-18 01:30:00         2

SELECT COUNT(DISTINCT users) AS ctUsers, checkout
FROM license_granted
GROUP BY checkout 

What I would like to get is:

checkout_time            ctUsers     userlist
2014-11-18 01:00:00         2        Bob,Steve
2014-11-18 01:30:00         2        Bob,Chris

Can this be done in the query?

Thanks

UPDATE 11/20 Okay I dug a little further and found a solution that gives me the checkout time and the userlist. Now I am trying to figure out how to count the elements in the userlist:

SELECT a.ctDate, SUBSTRING(d.users,1, LEN(d.users) - 1) usersList, count(d.users) AS ctUsers
FROM  (
   SELECT DISTINCT convert(varchar(10), deniedTime, 126) AS ctDate
    FROM hyperworks_checkouts
    ) a
    CROSS APPLY
    (
        SELECT DISTINCT [username] + ', ' 
        FROM hyperworks_checkouts AS B 
        WHERE A.ctdate = convert(varchar(10), deniedTime, 126)
        FOR XML PATH('')
    ) d (users)

The output now looks like this:

ctDate        usersList
2014-01-15    Bob
2014-01-16    Steve,Bob
2014-01-17    Mike,Chris,Jerry

If I try adding COUNT(d.users) in the Select I get a count of 1 each time because there is one list. How do I count the users in d.users?

Thanks

Answer 1

I found a solution. After looking at a few postings I was able to piece together the solution I needed:

SELECT a.ctDate, SUBSTRING(d.users,1, LEN(d.users) - 1) usersList, 
    (select len(d.users) - len(replace(d.users, ',', ''))) AS ctUsers
FROM  (SELECT DISTINCT convert(varchar(10), deniedTime, 126) AS ctDate
    FROM hyperworks_denials
    ) a
    CROSS APPLY
    (
        SELECT DISTINCT [username] + ', ' 
        FROM hyperworks_denials AS B 
        WHERE A.ctdate = convert(varchar(10), deniedTime, 126)
        FOR XML PATH('')
    ) d (users) 

Thanks everyone that gave suggestions

Answer 2

I think the GROUP_CONCAT function is what you are looking for.

So for your example, try:

SELECT COUNT(DISTINCT users) AS ctUsers, checkout, GROUP_CONCAT(DISTINCT users)
FROM license_granted
GROUP BY checkout

You can also define a custom separator for the GROUP_CONCAT values by adding a SEPARATOR clause inside the GROUP_CONCAT query, ie. GROUP_CONCAT(DISTINCT users SEPARATOR ' '

Answer 3

Try following query

SELECT COUNT(DISTINCT users) AS ctUsers, checkout,to_char(wm_concat(users)) Name
FROM license_granted
GROUP BY checkout