Francisco Olarte <folarte@xxxxxxxxxxxxxx> writes: > Hi Nelson: > On Wed, Jan 8, 2014 at 4:54 PM, Nelson Green <nelsongreen84@xxxxxxxxx> wrote: >> I have a projects log table with a three column PK, project_num, person_num, >> and sequence, where each new entry for a project/person combination >> increments the sequence, which is not an auto incrementing sequence. Is >> there any way to retrieve the last entry to the table? For instance, if the >> last entry for person 427 on project 15 was sequence number 125, is that >> information available to me anywhere? > SELECT MAX(sequence) FROM project_log_table WHERE person_num=427 AND > project_num=15 Note that this will not work terribly well if there are concurrent insertions for the same person/project. If that's not an issue, though, it should be fine. It may be OK even if there are sometimes concurrent insertions, if you are prepared to retry duplicate-key failures. > If it's a PK it should have an index and I believe it will be quite fast. It will be fast as long as sequence is the low-order column in the index. regards, tom lane -- Sent via pgsql-general mailing list (pgsql-general@xxxxxxxxxxxxxx) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-general
