Re: Unable to set guc via setProperty

On Fri, 20 Jun 2025 at 10:23, David G. Johnston <david(dot)g(dot)johnston(at)gmail(dot)com>
wrote:

> On Friday, June 20, 2025, Manav Kumar <mkumar(at)yugabyte(dot)com> wrote:
>
>> Hi Team,
>> I've a doubt regarding passing guc variables in start up packet as key
>> value pairs instead of in options.
>>
>> I'm unable to set jdbc:postgresql://10.150.3.175:6433/postgres?&geqo=off
>> m geqo to 'off'. I don't want to use "options" rather pass directly key
>> value pairs similar to what JDBC driver internally does.
>>
>
>> Neither setProperty("geqo", "off") works in this case.
>> Can someone let me know why I can't do it?
>>
>
> Probably because that isn’t how things work…connection properties are set
> using set property and gucs aren’t connection properties - though there is
> a pass-through connection property called options that can hold a list of
> gucs to set.
>
David, for my elucidation are they GUC's ? The docs state:
"Command-line arguments for the backend. (This is deprecated in favor of
setting individual run-time parameters.) Spaces within this string are
considered to separate arguments, unless escaped with a backslash (\);
write \\ to represent a literal backslash."

>
>
>>
>> I learnt or from code, it's seen the key value pairs has
>> higher precedence or override the guc values passed via cmdline
>> option("options") field when both passed in start up packet.
>> That's why with JDBC, even i try to set "options - DateStyle to
>> 'Postgres,DM'Y'" we are unable to change value as DateStyle is also passed
>> as key value by driver with 'ISO' which has higher precedence.
>>
>>
> IIUC the driver must control date style to operate correctly. And as a
> user you shouldn’t care because you’ll be using Java classes to process
> dates.
>

Yes, we set the datestyle to be able to interpret it correctly. You can
always change the datestyle to display.

Dave

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>