On Wed, Jan 9, 2019 at 12:26 PM Rob Sargent <robjsarg...@gmail.com> wrote:
> > > On Jan 9, 2019, at 11:11 AM, github kran <githubk...@gmail.com> wrote: > > Rob - It's a Java based application. We dont have triggers yet on the > table and is trigger a only option in 9.6 version ?. > > On Wed, Jan 9, 2019 at 12:01 PM Rob Sargent <robjsarg...@gmail.com> wrote: > >> >> On 1/9/19 10:21 AM, github kran wrote: >> >> Thanks for your reply Rob. Reading the below documentation link says the >> EVENT trigger is only supported for DDL commands. Is it not correct ?. >> >> *1) https://www.postgresql.org/docs/9.6/event-trigger-definition.html >> <https://www.postgresql.org/docs/9.6/event-trigger-definition.html> * >> (An event trigger fires whenever the event with which it is associated >> occurs in the database in which it is defined. Currently, the only >> supported events are ddl_command_start, ddl_command_end, table_rewrite >> and sql_drop. Support for additional events may be added in future >> releases.). >> 2) Doesnt the trigger slow down inserts/update we are doing to the table >> ?. Does it slow down if we are reading the data using the API when we have >> a trigger in place ?. >> >> >> Ah, right you are. Are triggers off the table? You would want to write >> the trigger function in some (trusted?) language with access to the outside >> > > (Custom here is to “bottom post”) > > Have you tried triggers and found them to have too much impact on total > system? I can’t see them being more expensive than looking for changes > every 5 seconds. If your hardware can scan 1T that quickly then I suspect > your trigger will not be noticed. I would have the trigger write to queue > and have something else using the queue to talk to IOT piece. > > Failing that, perhaps your java (server-side?) app making the changes can > be taught to emit the necessary details to IOT-thingy? > *Sure will try with a trigger and send data to a Queue and gather data for every 5 seconds reading off from the queue and send to IOT topic. Already we have a queue where every message inserted or updated on the table is sent to a queue but **that is lot of data we are gathering. We want to rather minimize collecting data from DB.*
