Thread

1. How to know if all insertions are finished

   intmail01 <intmail01@gmail.com> — 2024-03-08T12:01:11Z

   Hi,
   
   Is there any way to know if several insertion are terminated.
   I use libreoffice base to import at the same time many lines. When all
   lines are inserted I have to do some data check. I dont find any way to
   know if the insertion ends to start some function automatically.
   I tried to use a STATEMENT trigger type but all lines are treated as
   statement.
   

2. Re: How to know if all insertions are finished

   Steve Midgley <science@misuse.org> — 2024-03-08T16:26:21Z

   On Fri, Mar 8, 2024 at 4:01 AM intmail01 <intmail01@gmail.com> wrote:
   
   > Hi,
   >
   > Is there any way to know if several insertion are terminated.
   > I use libreoffice base to import at the same time many lines. When all
   > lines are inserted I have to do some data check. I dont find any way to
   > know if the insertion ends to start some function automatically.
   > I tried to use a STATEMENT trigger type but all lines are treated as
   > statement.
   >
   
   I think you are saying in your last line that each insert line is treated
   as an individual statement, so you get a bunch of trigger notifications
   instead of just one, and you don't know how to detect when you have
   received the final insert?
   
   The first thing I'd look for is whether I could wrap all the libreoffice
   inserts into a single transaction block, and then event off of the
   transaction block completing.
   
   Barring that, and noting I'm not familiar with how libreoffice would send
   the inserts, one option could be to put a listen/notify pattern at the end
   of your insert code, if it's possible to add a line of sql at the end of
   the inserts? Of course, if you can do that, you might also be able to wrap
   the whole thing with a transaction, but listen/notify might be simpler to
   event off of..
   
   -- In session/connection 1
   BEGIN;
   -- Perform your bulk insert operation here
   COMMIT;
   NOTIFY inserts_done;
   
   -- In session/connection 2
   LISTEN inserts_done;
   -- Once notification is received, proceed with necessary operations
   
   If you can't do something like this, the only other (relatively horrible)
   things I can think of would be to:
   
      1. Put a dummy row at the end of your insert data (if you can guarantee
      it would be inserted last during the bulk operation), and then build a
      trigger/condition to detect insertion of a row matching the dummy data that
      deletes the dummy row and then proceeds to kick off whatever other
      processes you want, or:
      2. Use a time based model, where you build an understanding of how long
      your inserts take to execute, and build a monitor that kicks off on each
      insert, and if another insert is not detected within a certain amount of
      wait time, you conclude that there are no more inserts coming, and you then
      kick off whatever other processes you want..
   
   Hopefully someone with deeper Postgres knowledge has other, more reliable
   solutions that leverage Postgres, but if your inserts are all discrete, and
   you don't have control over the sql itself.
   
   Steve
   

3. How to know if all insertions are finished

   Wetmore, Matthew (CTR) <matthew.wetmore@evernorth.com> — 2024-03-08T16:52:18Z

   Begin work
   Select count(*) prior to insert.
   Insert  from file
   Select count post insert
   If new count  matches old count + new rows from insert file
   Commit/rollback
   
   From: Steve Midgley <science@misuse.org>
   Sent: Friday, March 8, 2024 8:26 AM
   To: intmail01 <intmail01@gmail.com>
   Cc: pgsql-sql@lists.postgresql.org
   Subject: [EXTERNAL] Re: How to know if all insertions are finished
   
   
   
   On Fri, Mar 8, 2024 at 4:01 AM intmail01 <intmail01@gmail.com<mailto:intmail01@gmail.com>> wrote:
   Hi,
   
   Is there any way to know if several insertion are terminated.
   I use libreoffice base to import at the same time many lines. When all lines are inserted I have to do some data check. I dont find any way to know if the insertion ends to start some function automatically.
   I tried to use a STATEMENT trigger type but all lines are treated as statement.
   
   I think you are saying in your last line that each insert line is treated as an individual statement, so you get a bunch of trigger notifications instead of just one, and you don't know how to detect when you have received the final insert?
   
   The first thing I'd look for is whether I could wrap all the libreoffice inserts into a single transaction block, and then event off of the transaction block completing.
   
   Barring that, and noting I'm not familiar with how libreoffice would send the inserts, one option could be to put a listen/notify pattern at the end of your insert code, if it's possible to add a line of sql at the end of the inserts? Of course, if you can do that, you might also be able to wrap the whole thing with a transaction, but listen/notify might be simpler to event off of..
   
   -- In session/connection 1
   BEGIN;
   -- Perform your bulk insert operation here
   COMMIT;
   NOTIFY inserts_done;
   
   -- In session/connection 2
   LISTEN inserts_done;
   -- Once notification is received, proceed with necessary operations
   
   If you can't do something like this, the only other (relatively horrible) things I can think of would be to:
   
     1.  Put a dummy row at the end of your insert data (if you can guarantee it would be inserted last during the bulk operation), and then build a trigger/condition to detect insertion of a row matching the dummy data that deletes the dummy row and then proceeds to kick off whatever other processes you want, or:
     2.  Use a time based model, where you build an understanding of how long your inserts take to execute, and build a monitor that kicks off on each insert, and if another insert is not detected within a certain amount of wait time, you conclude that there are no more inserts coming, and you then kick off whatever other processes you want..
   Hopefully someone with deeper Postgres knowledge has other, more reliable solutions that leverage Postgres, but if your inserts are all discrete, and you don't have control over the sql itself.
   
   Steve
   

4. Re: How to know if all insertions are finished

   intmail01 <intmail01@gmail.com> — 2024-03-09T17:11:28Z

   >I think you are saying in your last line that each insert line is treated
   as an individual statement, so you get a bunch of trigger notifications
   instead of just one, and >you don't know how to detect when you have
   received the final insert?
   Yes. That is the problem.
   
   I do not code to insert data, it is done by drag/move from calc sheet to
   table graphically.
   
   The dummy row may be the solution with the risk you mention.
   
   Thanks.
   
   On Fri, Mar 8, 2024 at 7:27 PM Steve Midgley <science@misuse.org> wrote:
   
   >
   >
   > On Fri, Mar 8, 2024 at 4:01 AM intmail01 <intmail01@gmail.com> wrote:
   >
   >> Hi,
   >>
   >> Is there any way to know if several insertion are terminated.
   >> I use libreoffice base to import at the same time many lines. When all
   >> lines are inserted I have to do some data check. I dont find any way to
   >> know if the insertion ends to start some function automatically.
   >> I tried to use a STATEMENT trigger type but all lines are treated as
   >> statement.
   >>
   >
   > I think you are saying in your last line that each insert line is treated
   > as an individual statement, so you get a bunch of trigger notifications
   > instead of just one, and you don't know how to detect when you have
   > received the final insert?
   >
   > The first thing I'd look for is whether I could wrap all the libreoffice
   > inserts into a single transaction block, and then event off of the
   > transaction block completing.
   >
   > Barring that, and noting I'm not familiar with how libreoffice would send
   > the inserts, one option could be to put a listen/notify pattern at the end
   > of your insert code, if it's possible to add a line of sql at the end of
   > the inserts? Of course, if you can do that, you might also be able to wrap
   > the whole thing with a transaction, but listen/notify might be simpler to
   > event off of..
   >
   > -- In session/connection 1
   > BEGIN;
   > -- Perform your bulk insert operation here
   > COMMIT;
   > NOTIFY inserts_done;
   >
   > -- In session/connection 2
   > LISTEN inserts_done;
   > -- Once notification is received, proceed with necessary operations
   >
   > If you can't do something like this, the only other (relatively horrible)
   > things I can think of would be to:
   >
   >    1. Put a dummy row at the end of your insert data (if you can
   >    guarantee it would be inserted last during the bulk operation), and then
   >    build a trigger/condition to detect insertion of a row matching the dummy
   >    data that deletes the dummy row and then proceeds to kick off whatever
   >    other processes you want, or:
   >    2. Use a time based model, where you build an understanding of how
   >    long your inserts take to execute, and build a monitor that kicks off on
   >    each insert, and if another insert is not detected within a certain amount
   >    of wait time, you conclude that there are no more inserts coming, and you
   >    then kick off whatever other processes you want..
   >
   > Hopefully someone with deeper Postgres knowledge has other, more reliable
   > solutions that leverage Postgres, but if your inserts are all discrete, and
   > you don't have control over the sql itself.
   >
   > Steve
   >