Sorry corrected value in Table B

Thorsten Knopel wrote:
> hello , i need some help for a complicate sql search, hope someone can
> help me
>
>
> Problem:
>
> Table A: mega_grp, grp
> ----------------------
>
> e.g. mg1, grp1
> mg1, grp2
> mg2, grp3
> -----------------------
>
> Table B: user, grp
> ----------------------
> e.g. usr1, grp1
> usr1, grp2
> usr2, grp1
> usr2, grp3
> ----------------------
>
>
> What we want is to find all user which are in mega_group "mg1". That
> mean all user which are in "grp1" and "grp2". Not only in one but in
> both. In the example it would be only "usr1" because "usr2" is not in
> "grp2"
>
>
> I tried it with a subselect and an IN Operation but then i get all user
> which are in one of the groups but not in both.
>
>
> Thanxs for your help
>
> Thorsten