Horton

Re: Retrieving query results

Igor Korot <ikorot01@gmail.com>

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From: Igor Korot <ikorot01@gmail.com>
To: Michael Paquier <michael.paquier@gmail.com>
Cc: pgsql-general <pgsql-general@postgresql.org>
Date: 2017-08-23T01:04:05Z
Lists: pgsql-general 
Hi, Michael,

On Tue, Aug 22, 2017 at 8:32 PM, Michael Paquier
<michael.paquier@gmail.com> wrote:
> On Wed, Aug 23, 2017 at 3:19 AM, Igor Korot <ikorot01@gmail.com> wrote:
>> [quote]
>> PQntuples
>>
>> Returns the number of rows (tuples) in the query result. Because it
>> returns an integer result, large result sets might overflow the return
>> value on 32-bit operating systems.
>>
>> int PQntuples(const PGresult *res);
>>  [/quote]
>>
>> Is there another way to not to overflow the result?
>
> Not really with the existing API.


What do you mean "not really"

> Note that getting at 2 billion rows
> is really a lot, and would cause performance issues on the application
> side because a bunch of data would need to be processed, and getting
> out this much data is not network-wise anyway.

That's OK, As long as my program works with arbitrary number of rows.

Thank you.

> --
> Michael

Commits

  1. Doc: document libpq's restriction to INT_MAX rows in a PGresult.

  2. Teach libpq to detect integer overflow in the row count of a PGresult.