Question

I’m looking to write a query that grabs a count of a field and groups it together, but I want it to return ALL values even if the count is 0.

Here’s what I have:

SELECT COUNT(*)
      ,PMI
  FROM Items AS AA
  JOIN Headers AS BB
  ON AA.DocID = BB.ID
 WHERE (DocDate = CAST(CONVERT(varchar(8), GETDATE() - 1, 1) AS datetime))
   AND PMI != ''
GROUP BY PMI

Here’s what I want to see:

COUNT     PMI
    1     900330
    5     900702
    0     900550
    0     900331

But here’s what I’m getting:

COUNT     PMI
    1     900330
    5     900702

I’ve never had to write a query to accomplish this before so I apologize if this is trivial.

EDIT: I realized that these tables do not contain all of the items I am looking for. I have a lookup table called ‘lookup’ which contains all of these items I wish to query for counts.

EDIT 2: Thanks everyone. Made it work by creating a view and using the lookup table and an outer join. Did the trick wonderfully.

Answer 1

You are using an INNER JOIN which returns no row if the match fials. You should use an OUTER JOIN instead.

Assuming that PMI is on Items:

SELECT PMI, COUNT(BB.ID)
  FROM Items AS AA
  LEFT JOIN Headers AS BB
  ON AA.DocID = BB.ID
 WHERE (DocDate = CAST(CONVERT(varchar(8), GETDATE() - 1, 1) AS datetime))
   AND PMI != ''
GROUP BY PMI