Thread: 9.0+ way of determining if a LISTEN channel has a backend listening?

9.0+ way of determining if a LISTEN channel has a backend listening?

From

James Robinson

Date:

01 June 2011, 16:10:37

Is there a way in post-9.0 postgres for one session to determine if a  
LISTEN channel currently has a backend registered to receive  
notifications? Prior to 9.0, one could select from system catalog  
table pg_listener.

Function pg_listening_channels() returns list of symbol names *this*  
session is listening on; I'd like to find out if a given listen  
channel has *any* (i.e other session) listeners.

Thanks!
----
James Robinson
Socialserve.com

Re: 9.0+ way of determining if a LISTEN channel has a backend listening?

From

"Greg Sabino Mullane"

Date:

01 June 2011, 22:22:53

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> Is there a way in post-9.0 postgres for one session to determine if a  
> LISTEN channel currently has a backend registered to receive  
> notifications?

No, there is no way. As mentioned on a similar thread on -hackers, 
you could possibly use advisory locks if you really need to 
know what another session is listening to.

- -- 
Greg Sabino Mullane greg@turnstep.com
End Point Corporation http://www.endpoint.com/
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