Re: Using the dollar sign as a prefix for named parameter of prepared statement.

Dmitry Igrishin <dmitigr(at)gmail(dot)com> writes:
> I'm working on finishing beta release of my C++ API for PostgreSQL. The
> library
> have simple SQL parser (preprocessor) to support the queries like that:

> SELECT :"column", $tag$constant string$tag$
> FROM :tables
> WHERE name LIKE :'name' AND
> sex = $1 AND
> age > $age

> where:
> :"column" is a variable which will be quoted as identifier (like in
> psql),
> :tables is a variable which will be not be quoted at all (like in psql),
> :'name' is a variable which will be quoted as literal (like in psql),
> $1 is a positional parameter,
> $age is a named parameter

> Is there are any contraindications/caveats/gotchas on using the dollar sign
> as a prefix for the named parameters?

How are you going to distinguish named parameters from dollar-quote tags?
For instance, this is legal:

regression=# select $foobar$stuff$foobar$;
?column?
----------
stuff
(1 row)

I think you're going to end up with weird corner case behaviors if
you try to squeeze still another meaning into "$letters..."

regards, tom lane