Where Not Exists with a twist.

[David Powell]

A little help here please.

Table
Location type Value
23 A 12.5
23 B 13.6
23 C 14.7
34 A 15.9
34 B 16.0
34 C 17.2
45 A 18.3
45 B 19.4

I must sum the values for each location, but only if I have as many types as the maximum number of types. So in this example, I have types A,B, and C so I only want to work on the two locations that have A,B, and C types. If a new row with a 4th type were added to the data, I'd only want to sum those rows with types A,B,C, and D.

I understand group by location.
I understand select sum(value)
I'll use select distinct(type) to come up with a complete list of individual types.

In this example I need to exclude location 45 data because it lacks data of type C.

I'm looking for something that does
Where there is location data for each of the types found in (select distinct(type)

How do I do that?

TIA, Dave