Re: [RFC] How about changing the default value of defaultRowFetchSize?

On 20 October 2016 at 13:30, Jorge Solórzano <jorsol(at)gmail(dot)com> wrote:

> On Thu, Oct 20, 2016 at 10:33 AM, Vladimir Sitnikov <
> sitnikov(dot)vladimir(at)gmail(dot)com> wrote:
>
>> Jorge>The value of 0 should be used to fetch all rows, if we ​leave the
>> default at 0 and handle internally that as 100 (and reporting it as 0) it
>> is a wrong behavior.
>>
>> Note that "unset" and "set to 0" might have different meanings for a good
>> (or bad?) reason.
>>
>>
>
> ​Yes, but "by default"​ is set to 0, not "unset (null)":
>
>> /**
>> * Default parameter for {(at)link java.sql.Statement#getFetchSize()}. A
>> value of {(at)code 0} means
>> * that need fetch all rows at once
>> */
>> DEFAULT_ROW_FETCH_SIZE("defaultRowFetchSize", "0",
>> "Positive number of rows that should be fetched from the database
>> when more rows are needed for ResultSet by each fetch iteration"),
>>
>
> ​So if the driver internally handle fetch size 0 == fetch size 100, that's
> what i call an hidden inconsistent behavior.
>
> Don't get me wrong, it make sense to switch ​defaultRowFetchSize to "100",
> but a call to getFetchSize() should be == 100, not 0.
>

As I said 99% of the code out there will never use this as fetch size is
totally useless in autocommit mode. Also an inconsistent behaviour. There a
lots of them.. Setting it internally is fine IMO. I also think it should be
reported as 0 unless the user explicitly sets it. What we do inside the
driver is our business.

Dave Cramer

davec(at)postgresintl(dot)com
www.postgresintl.com