SQL: multiple counts from same table - sql

Question

I am having a real problem trying to get a query with the data I need. I have tried a few methods without success. I can get the data with 4 separate queries, just can't get hem into 1 query. All data comes from 1 table. I will list as much info as I can.
My data looks like this. I have a customerID and 3 columns that record who has worked on the record for that customer as well as the assigned acct manager
RecID_Customer___CreatedBy____LastUser____AcctMan
1-------1374----------Bob Jones--------Mary Willis------Bob Jones
2-------1375----------Mary Willis------Bob Jones--------Bob Jones
3-------1376----------Jay Scott--------Mary Willis-------Mary Willis
4-------1377----------Jay Scott--------Mary Willis------Jay Scott
5-------1378----------Bob Jones--------Jay Scott--------Jay Scott
I want the query to return the following data. See below for a description of how each is obtained.
Employee___Created__Modified__Mod Own__Created Own
Bob Jones--------2-----------1---------------1----------------1
Mary Willis------1-----------2---------------1----------------0
Jay Scott--------2-----------1---------------1----------------1
Created = Counts the number of records created by each Employee
Modified = Number of records where the Employee is listed as Last User
(except where they created the record)
Mod Own = Number of records for each where the LastUser = Acctman
(account manager)
Created Own = Number of Records created by the employee where they are
the account manager for that customer
I can get each of these from a query, just need to somehow combine them:
Select CreatedBy, COUNT(CreatedBy) as Created
FROM [dbo].[Cust_REc] GROUP By CreatedBy
Select LastUser, COUNT(LastUser) as Modified
FROM [dbo].[Cust_REc] Where LastUser != CreatedBy GROUP By LastUser
Select AcctMan, COUNT(AcctMan) as CreatePort
FROM [dbo].[Cust_REc] Where AcctMan = CreatedBy GROUP By AcctMan
Select AcctMan, COUNT(AcctMan) as ModPort
FROM [dbo].[Cust_REc] Where AcctMan = LastUser AND NOT AcctMan = CreatedBy GROUP By AcctMan
Can someone see a way to do this? I may have to join the table to itself, but my attempts have not given me the correct data.

Answer 1

The following will give you the results you're looking for.
select
e.employee,
create_count=(select count(*) from customers c where c.createdby=e.employee),
mod_count=(select count(*) from customers c where c.lastmodifiedby=e.employee),
create_own_count=(select count(*) from customers c where c.createdby=e.employee and c.acctman=e.employee),
mod_own_count=(select count(*) from customers c where c.lastmodifiedby=e.employee and c.acctman=e.employee)
from (
select employee=createdby from customers
union
select employee=lastmodifiedby from customers
union
select employee=acctman from customers
) e
Note: there are other approaches that are more efficient than this but potentially far more complex as well. Specifically, I would bet there is a master Employee table somewhere that would prevent you from having to do the inline view just to get the list of names.

Answer 2

this seems pretty straight forward. Try this:
select a.employee,b.created,c.modified ....
from (select distinct created_by from data) as a
inner join
(select created_by,count(*) as created from data group by created_by) as b
on a.employee = b.created_by)
inner join ....

Answer 3

This highly inefficient query may be a rough start to what you are looking for. Once you validate the data then there are things you can do to tidy it up and make it more efficient.
Also, I don't think you need the DISTINCT on the UNION part because the UNION will return DISTINCT values unless UNION ALL is specified.
SELECT
Employees.EmployeeID,
Created =(SELECT COUNT(*) FROM Cust_REc WHERE Cust_REc.CreatedBy=Employees.EmployeeID),
Mopdified =(SELECT COUNT(*) FROM Cust_REc WHERE Cust_REc.LastUser=Employees.EmployeeID AND Cust_REc.CreateBy<>Employees.EmployeeID),
ModOwn =
CASE WHEN NOT Empoyees.IsManager THEN NULL ELSE
(SELECT COUNT(*) FROM Cust_REc WHERE AcctMan=Employees.EmployeeID)
END,
CreatedOwn=(SELECT COUNT(*) FROM Cust_REc WHERE AcctMan=Employees.EmployeeID AND CReatedBy=Employees.EMployeeID)
FROM
(
SELECT
EmployeeID,
IsManager=CASE WHEN EXISTS(SELECT AcctMan FROM CustRec WHERE AcctMan=EmployeeID)
FROM
(
SELECT DISTINCT
EmployeeID
FROM
(
SELECT EmployeeID=CreatedBy FROM Cust_Rec
UNION
SELECT EmployeeID=LastUser FROM Cust_Rec
UNION
SELECT EmployeeID=AcctMan FROM Cust_Rec
)AS Z
)AS Y
)
AS Employees

Answer 4

I had the same issue with the Modified column. All the other columns worked okay. DCR example would work well with the join on an employees table if you have it.
SELECT CreatedBy AS [Employee],
COUNT(CreatedBy) AS [Created],
--Couldn't get modified to pull the right results
SUM(CASE WHEN LastUser = AcctMan THEN 1 ELSE 0 END) [Mod Own],
SUM(CASE WHEN CreatedBy = AcctMan THEN 1 ELSE 0 END) [Created Own]
FROM Cust_Rec
GROUP BY CreatedBy