Is this "invoice_number" just an id or what might appear an a bill (in some pretty form etc)? If the former, just get a unique id over all invoices. At the very least it will save time i) in writing where clauses ii) re-creating the correct id once some one assigns an invoice to the wrong customer. On 10/22/2010 01:18 PM, Michael Gardner wrote: > Consider the following table: > > CREATE TABLE invoice ( > account_id integer NOT NULL REFERENCES account, > invoice_number integer NOT NULL, > UNIQUE (account_id,invoice_number)); > > I would like to do the equivalent of making invoice_number a serial type, but on a per-account basis. Would it be a reasonable approach to create a separate sequence for each individual account? Are there performance implications I should know about, given that there will be hundreds of thousands of accounts? Is there another approach I should be looking at instead? -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
