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Re: Anyone here do anything with libpq?

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From	Robert Klemme <shortcutter@googlemail.com>
Newsgroups	comp.databases.postgresql
Subject	Re: Anyone here do anything with libpq?
Date	Mon, 15 May 2017 19:54:50 +0200
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On 15.05.2017 16:41, DFS wrote:
> https://www.postgresql.org/docs/9.6/static/libpq.html
>
> Specifically, I'm curious about when/how often to clear a result set:
>
> <quote>
> PQclear
> Frees the storage associated with a PGresult. Every command result
> should be freed via PQclear when it is no longer needed.
>
> void PQclear(PGresult *res);
>
> You can keep a PGresult object around for as long as you need it; it
> does not go away when you issue a new command, nor even if you close the
> connection. To get rid of it, you must call PQclear. Failure to do this
> will result in memory leaks in your application.
> </quote>
>
> 'when it is no longer needed' sounds like it can be cleared once, at the
> end of the script.

What do you mean by "script"?  Aren't we talking about C or C++ here?

> If you have experience with this, did you feel like it was OK to clear
> it once at the end of the program, or every time before you used result
> object?

My advice is to clear it as soon as you do not need it any more.  This 
might be less important for a short running program but if you are 
writing some form of reusable code or a long running application then it 
is clearly advisable to rid of the data as soon as it is processed.  No 
point in holding on to memory longer than it is needed.

Kind regards

	robert

-- 
remember.guy do |as, often| as.you_can - without end
http://blog.rubybestpractices.com/

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Thread

Anyone here do anything with libpq? DFS <nospam@dfs.com> - 2017-05-15 10:41 -0400
  Re: Anyone here do anything with libpq? Rainer Weikusat <rweikusat@talktalk.net> - 2017-05-15 16:38 +0100
    Re: Anyone here do anything with libpq? DFS <nospam@dfs.com> - 2017-05-16 10:45 -0400
      Re: Anyone here do anything with libpq? Rainer Weikusat <rweikusat@talktalk.net> - 2017-05-16 20:52 +0100
  Re: Anyone here do anything with libpq? Robert Klemme <shortcutter@googlemail.com> - 2017-05-15 19:54 +0200
    Re: Anyone here do anything with libpq? DFS <nospam@dfs.com> - 2017-05-16 14:01 -0400
      Re: Anyone here do anything with libpq? Robert Klemme <shortcutter@googlemail.com> - 2017-05-16 23:04 +0200
      Re: Anyone here do anything with libpq? George Neuner <gneuner2@comcast.net> - 2017-05-17 08:40 -0400

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