Question

I am still fairly new to SQL so I wanted to know if I am doing this the most optimized way.

 SELECT DISTINCT ACCOUNTID, ACCOUNT_NAME
  (SELECT        COUNT(*)
  FROM            TICKET
  WHERE        (ACCOUNTID = OPPORTUNITY.ACCOUNTID)) AS [Number Of Tickets],
  (SELECT        COUNT(*)
  FROM            TICKET
  WHERE        (ACCOUNTID = OPPORTUNITY.ACCOUNTID) AND (STATUSCODE = 1 OR
         STATUSCODE = 2 OR
         STATUSCODE = 3)) AS [Active Tickets]
 from OPPORTUNITY
    where AccountID > @LowerBound and AccountID < @UpperBound

What I am trying to do is get a list of all accounts and have it show how many tickets the account has and how many are active (have a status code that is 1, 2, or 3). Is the select inside the select the correct way to do this or is there a way it can be done using something like group by.

My biggest concern is speed, it takes 3-5 seconds to just pull around 20 records and the query could potentially have 1000’s of results.

I am not the DBA so any changes to table schema are not imposable but will require some pleading with upper management.

This is being run against SQL Server 2000.

EDIT–
as all of the answers where asking about it I checked on it. Both Opportunity and ticket index on accountid ascending.

Answer 1

I think the below should be logically equivalent and more efficient. Obviously test both aspects your end!

 SELECT O.ACCOUNTID, O.ACCOUNT_NAME,
   COUNT(*) AS [Number Of Tickets],
   ISNULL(SUM(CASE WHEN STATUSCODE IN (1,2,3) THEN 1 ELSE 0 END),0) 
                                                                AS [Active Tickets]
 FROM OPPORTUNITY O
 LEFT OUTER JOIN TICKET T ON T.ACCOUNTID = O.ACCOUNTID
    WHERE O.ACCOUNTID > @LowerBound and O.ACCOUNTID < @UpperBound
    GROUP BY O.ACCOUNTID, O.ACCOUNT_NAME

IF you can view the execution plans then you should check indexes exist on ACCOUNTID in both tables and are being used.