" SELECT m.*, c.*

FROM master m

INNER JOIN child c

ON m.m1 = c.c1

AND m.m2 = c.c2 "

is there any thing wrong or less professional in Coding as

ELECT m.*, c.*

FROM...

No NO

You please reply, It's OK .

I can convert the Queries to Postgres after all its all SQL99

Oh Oh. I Think I got confused. Isn't primary ket just one field.

OK there is composite key. i.e two fields will act as a primary key

then how...

I am using Postgres Sql in Linux.

So ...

True

But I am getting opions such as in case of the Sales Table

The Sales Mater Key and the Product Id will act as a Composite key to identify...

Thank U

That just Works Fine

But just as you said it can't be scaled to find the n'th Largest Element