Question

Hi maybe someone can help me here …
I have a slight problem with an SQL Statement. ( On MS – SQL Server 2008)
So i have 6 Tables looking like this

ID / Company / Month / ClosedTimeStamp / Different Information

Now i need (preferrable in one Statement :P) the count of Datasets from each table grouped by Company and Month at the time it looks something like this.
And there is another thing not all tables need to have data for that Company and that Month so there can be 0 as Result for count(*)

SELECT COUNT(*) as c, Month, Company 
FROM Table1  WHERE ClosedTimeStamp IS NULL
GROUP BY Company, Month 
ORDER BY Company

I can do this for all the tables and just pick out the results for each company … Well if someone has any Idea i really would appreciate it 🙂

Sorry forgot something … the result should look like this:

Company / Month / CountTable1 / CountTable2 / CountTable3 / …..
Test 02 1 0 50

If it’s not possible in one statement well then i have to make it work another way. 🙂

Thanks

Lim

Answer 1

If your DB was normalized the query would be much simpler.

Because, your company and Month are spread across 6 tables, we need to make union of those tables in order to get the distinct dataset of all company+month, as such:

select company, month from table1
 union
select company, month from table2
 union
select company, month from table3
 union
select company, month from table4
 union
select company, month from table5
 union
select company, month from table6

Note, that we need union, not union all, because we don’t want the same company+month pair repeated.

Then, just use this dataset to query the quantities for each table:

select t.company, t.month,
    (select count(*) from table1
      where company = t.company
        and month = t.month
        and ClosedTimeStamp is null) as qt1,
    (select count(*) from table2 
      where company = t.company
        and month = t.month
        and ClosedTimeStamp is null) as qt2,
    (select count(*) from table3
      where company = t.company 
        and month = t.month
        and ClosedTimeStamp is null) as qt3,
    (select count(*) from table4
      where company = t.company
        and month = t.month
        and ClosedTimeStamp is null) as qt4,
    (select count(*) from table5
      where company = t.company
        and month = t.month
        and ClosedTimeStamp is null) as qt5,
    (select count(*) from table6
      where company = t.company
        and month = t.month
        and ClosedTimeStamp is null) as qt6
from (
  select company, month from table1
   union
  select company, month from table2
   union
  select company, month from table3
   union
  select company, month from table4
   union
  select company, month from table5
   union
  select company, month from table6
) t
order by t.company