Hi, guys, On Mon, Jul 9, 2018 at 5:38 PM, Adrian Klaver <adrian.klaver@xxxxxxxxxxx> wrote: > On 07/09/2018 01:49 PM, Igor Korot wrote: >> >> Hi, Adrian >> >> On Tue, Jul 3, 2018 at 1:24 PM, Adrian Klaver <adrian.klaver@xxxxxxxxxxx> >> wrote: >>> >>> On 07/03/2018 11:15 AM, Igor Korot wrote: >>>> >>>> >>>> Adrian, >>>> >>>> On Tue, Jul 3, 2018 at 12:32 PM, Adrian Klaver >>>> <adrian.klaver@xxxxxxxxxxx> wrote: >>>>> >>>>> >>>>> On 07/03/2018 10:21 AM, Igor Korot wrote: >>>>>> >>>>>> >>>>>> >>>>>> Hi, ALL, >>>>>> Is there any trigger or some other means I can do on the server >>>>>> which will watch for CREATE/ALTER/DROP TABLE command and after >>>>>> successful >>>>>> execution of those will issue a NOTIFY statement? >>>>> >>>>> >>>>> >>>>> >>>>> https://www.postgresql.org/docs/10/static/event-triggers.html >>>> >>>> >>>> >>>> According to the documentation the lowest version it supports is 9.3. >>>> Anything prior to that? >>>> >>>> I'm working with OX 10.8 and it has 9.1 installed. >>> >>> >>> 9.1 went EOL almost two years ago. The oldest supported version is 9.3, >>> though it will go EOL this September: >>> >>> https://www.postgresql.org/support/versioning/ >>> >>> Are you forced to work with 9.1 or can you use something from here: >>> >>> https://www.postgresql.org/download/macosx/ >>> >>> to get a newer version? FYI that will be a major upgrade so will require >>> a >>> dump/restore or use of pg_upgrade. >> >> >> Just a thought... >> Is it possible to create a trigger for a system table? Or this >> operation is restricted > > > Easy enough to test. As postgres super user: > > test_(postgres)# create trigger info_test before insert on pg_class execute > procedure ts_update(); > > ERROR: permission denied: "pg_class" is a system catalog But draft=# CREATE TRIGGER info_test AFTER INSERT ON information_schema.tables EXECUTE PROCEDURE test(); ERROR: function test() does not exist So it looks like this should be possible? Thank you. > > >> for when the server is actually being set-up? >> >> Successful "CREATE TABLE..." statement creates a row inside the >> information_schema.tables >> so if I can create a trigger after this record is inserted or deleted >> that should be fine. >> >> Thank you. >> >>> >>>> >>>> And a second question - how do I work with it? >>>> I presume that function will have to be compiled in its own module >>>> (either dll, so or dylib). >>>> But then from the libpq interface how do I call it? >>> >>> >>> >>> It can use functions written in PL languages. See below: >>> >>> https://www.postgresql.org/docs/10/static/sql-createeventtrigger.html >>> >>> for an example written in plpgsql. >>> >>> >>> >>> >>> >>>> >>>> Thank you. >>>> >>>>> >>>>>> >>>>>> Thank you. >>>>>> >>>>> >>>>> >>>>> -- >>>>> Adrian Klaver >>>>> adrian.klaver@xxxxxxxxxxx >>> >>> >>> >>> >>> -- >>> Adrian Klaver >>> adrian.klaver@xxxxxxxxxxx > > > > -- > Adrian Klaver > adrian.klaver@xxxxxxxxxxx
