On Thursday, December 4, 2025, Rich Shepard <[email protected]> wrote:
> I want the script to extract only the maximum `next_contact' date and > haven't learned how to do this from my reading of web sites. > > The script: > > select p.person_nbr, p.company_nbr, c.next_contact > from people as p, contacts as c > where c.next_contact >= '2025-11-01' > group by p.person_nbr, p.company_nbr, c.next_contact > order by p.person_nbr, p.company_nbr, max(c.next_contact); > > returns all contacts rather than only the latest one. > > Is using a sub-select the proper way? > I would go with a lateral join subquery of the contracts table. Using an aggregates to perform ranking is an anti-pattern. You want the contract ranked first when ordered by contract_date. Either use a window function to explicitly rank the contracts or use a limit/fetch clause to simply return the first ordered one. You also seem to have completely missed joining people to contracts - suggest using explicit “join” clauses to make that error less likely. David J.
