Question

I have this table that has 2 columns:

ID, TypeID

Each ID can have multiple TypeIDs. In the query result i want to have the following:

ID, Count(TypeID = 10), Count(TypeID = 20 or 30), Count(TypeID 40 and 50)

The query itself should be as fast / performant as possible. Can anyon help?

Answer 1

Try this:

SELECT 
  ID,
  SUM(CASE WHEN TypeID = 10 THEN 1 ELSE 0 END) "Count of 10",
  SUM(CASE WHEN TypeID IN (20, 30) THEN 1 ELSE 0 END) "Count of 30 or 20",
  SUM(CASE WHEN TypeID IN (40, 50) THEN 1 ELSE 0 END) "Count of 40 AND 50"
FROM Table
GROUP BY ID;

For the last case: Count(TypeID 40 and 50) I think the predicate TypeID IN (40, 50) will work for you, since it will give the count of values 40 and 50.

SQL Fiddle Demo