Re: docs: psql and variable interpolation

Le 13/07/2020 à 17:45, David G. Johnston a écrit :
> On Monday, July 13, 2020, Philippe Beaudoin
> <philippe(dot)beaudoin(at)dalibo(dot)com <mailto:philippe(dot)beaudoin(at)dalibo(dot)com>>
> wrote:
>
> The first sentence of this SQL interpolation chapter says "A key
> feature of psql variables is that you can substitute
> (“interpolate”) them into regular SQL statements, as well as the
> arguments of meta-commands." But nothing in this chapter indicates
> that there are exceptions.
>
> May be we could have a wording adjustment with something like : "A
> key feature of psql variables is that you can substitute
> (“interpolate”) them into regular SQL statements, as well as the
> arguments of meta-commands (unless specifically noted)."
>
>
> Having “unless otherwise noted” be implied doesn’t seem like a big
> failing.  As for this case it is documented as being an exception:
>
> “Unlike most other meta-commands, the entire remainder of the line is
> always taken to be the arguments of |\copy|, and neither variable
> interpolation nor backquote expansion are performed in the arguments.”
>
> If it is only \copy that is an exception I’d rather just say (except
> \copy} and not have the user meticulously read each item for the
> single exception.  This extends to if there are a few.

As far as I know, the \! metacommand is another exception. But I don't
know if there are some others.

>
> David J.
>
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