Re: Allow default \watch interval in psql to be configured

On 09/10/2024 16:08, Daniel Gustafsson wrote:
> Scratching an old itch; I've long wanted to be able to set the default interval
> for \watch in psql since I almost never want a 2 second wait.  The interval can
> of course be set by passing it to \watch but it's handy during testing and
> debugging to save that with just quick \watch.
> 
> The attached adds a new variable, WATCH_INTERVAL, which is used as the default
> value in case no value is defined when executing the command.  The defualt of
> this remains at 2 seconds as it is now.  The count and min_rows values are not
> affected by this as those seem less meaningful to set defaults on.

../src/bin/psql/startup.c:953:80: error: too many arguments to function 
call, expected 4, have 5
         return ParseVariableDouble(newval, "WATCH_INTERVAL", 
&pset.watch_interval, 0, 1000);
                ~~~~~~~~~~~~~~~~~~~ 
               ^~~~
../src/bin/psql/variables.h:84:7: note: 'ParseVariableDouble' declared here
bool            ParseVariableDouble(const char *value, const char *name,
                 ^
1 error generated.

I guess the '1000' was supposed to be the maximum, but 
ParseVariableDouble doesn't take a maximum.

After fixing that by removing the '1000' argument:


postgres=# \set WATCH_INTERVAL -10
invalid value "-10" for "WATCH_INTERVAL": must be greater than 0.00

That's a little inaccurate: 0 is also accepted, so should be "must be 
greater than *or equal to* 0". Or maybe "cannot be negative". -0 is also 
accepted, though.

> +        This variable set the default interval which <command>\watch</command>

set -> sets

> +       HELP0("  WATCH_INTERVAL\n"
> +                 "    number of seconds \\watch waits beetween queries\n");

beetween -> between

-- 
Heikki Linnakangas
Neon (https://neon.tech)