in practice, there's no difference... from the postgres docs (http:// www.postgresql.org/docs/8.4/static/sql-select.html) -
USING ( join_column [, ...] ) A clause of the form USING ( a, b, ... ) is shorthand for ON left_table.a = right_table.a AND left_table.b = right_table.b .... Also, USING implies that only one of each pair of equivalent columns will be included in the join output, not both. so in your example you'd only get a single "id" column in the output rather than 1 from each of the employees and managers tables... On Sep 29, 4:24 pm, Clive Crous <[email protected]> wrote: > If I may I'd like to ask a SQL question here. > > What is the difference between: > > SELECT * FROM employees > INNER JOIN managers USING (id); > > and > > SELECT * FROM employees > INNER JOIN managers ON managers.id=employees.id; > > ? > > Thanks, > Clive --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sequel-talk" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/sequel-talk?hl=en -~----------~----~----~----~------~----~------~--~---
