Hello @sql-experts,
I have solved a n:m relation by generating a lookup table.

Table1:
- T1_ID

Table2:
- T2_ID

Table3 (LookUp):
- T1_ID
- T2_ID

The Table3 has data, like:
T1_ID -- T2_ID
1 -- 1
1 -- 2
1 -- 3
2 -- 2
2 -- 3
2 -- 4

Now I need a select statement to find all T1_ID's which have 1 or more
T2_ID, e.g T2_ID=2 and T2_ID=3.

So is it possible to create a where clause over all rows?

kind regards
Matthias