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Count statement with group...

Posted on 2014-12-17
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Last Modified: 2014-12-18
Hello, can someone let me know how I can write a statement that firsts groups by column A and then give a count of values in column B. For eg;
Col-A(Cust ID)         Col-B
100                          Closed
200                          Active  
200                          Active
100                          Closed
300                          Open
400                          Progress
500                          Active

Output I am looking for is:
Col-B   count
Closed  1
Active    2
Open     1
Progress 1

Thanks for the help.

A
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Question by:aej1973
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5 Comments
 
LVL 66

Expert Comment

by:Jim Horn
ID: 40506257
> firsts groups by column A and then give a count of values in column B.
Not quite sure I'm following your logic here, as the sample data set doesn't translate to the data mockup.  
There are seven rows in your sample data set, and only five in the result set.
Select ColB, COUNT(ColB) as the_count
FROM YourTable
GROUP BY ColB

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0
 

Author Comment

by:aej1973
ID: 40506280
I am sorry if I did not make myself clear. Let me explain;

The first grouping should be with reference to  Col-A. So the outcome would be:
Col-A Col-B
100    Closed
200    Active
300    Open
400    Progress
500   Active

The next grouping and count should be with reference to col-B, the output will be;
Col b      count
Closed     1
Active      2
Open       1
progress 1

How can these two steps be combined into one query? Thanks for taking a look at it.

A
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LVL 66

Accepted Solution

by:
Jim Horn earned 2000 total points
ID: 40506313
Okay, try this then:
IF OBJECT_ID('tempdb..#tmp') IS NOT NULL
   DROP TABLE #tmp
GO

CREATE TABLE #tmp (ColA int, ColB varchar(25)) 

INSERT INTO #tmp (ColA, ColB)
VALUES 
   (100, 'Closed'), (200, 'Active'),  (200, 'Active'),(100, 'Closed'),
   (300, 'Open'),(400, 'Progress'),(500, 'Active')

SELECT a.ColB, COUNT(a.ColB) as [Count]
FROM (
   Select ColA, ColB
   FROM #tmp
   GROUP BY ColA, ColB) a
GROUP BY a.ColB

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LVL 25

Expert Comment

by:chaau
ID: 40508156
All you need is to count DISTINCT values, like this:
Select ColB, COUNT(DISTINCT ColA) as the_count
FROM YourTable
GROUP BY ColB

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Author Closing Comment

by:aej1973
ID: 40508274
Works! Thank you.
0

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