Postgres @named parameters don't always work

[tv42]

Based on https://github.com/kyleconroy/sqlc/blob/master/docs/named_parameters.md
@foo and sqlc.arg(foo) are identical. However:

-- schema says create table foo ( id bigint );
-- name: demo1 :exec
DELETE FROM foo WHERE id=$1;
-- name: demo2 :exec
DELETE FROM foo WHERE id=@id;
-- name: demo3 :exec
DELETE FROM foo WHERE id=sqlc.arg(id);

results in

$ grep ^func demo.sql.go
func (q *Queries) demo1(ctx context.Context, id sql.NullInt64) error {
func (q *Queries) demo2(ctx context.Context) error {
func (q *Queries) demo3(ctx context.Context, id sql.NullInt64) error {

The @foo form doesn't get recognized in this scenario.

[kyleconroy]

I'm not sure why, but the @ form works when there's a space between the = and @. Take a look here: https://play.sqlc.dev/p/a2beb1f05746a8cac18a0d161645866c83f95896311b1e1b8ad5943199d7c5dd

Long term, I think I'm going to regret adding the @ form of named parameters because of issues like this.

[maxhawkins]

Sorry if this is digging up something that got settled in #71, but I wish the syntax was :param instead of @param. That way you could use psql to debug your queries against a running database:

psql --variable "param=1" -f queries.sql database

Unsure if using that syntax would help with the parsing problem here.

[kyleconroy]

@maxhawkins The :param syntax doesn't work with the MySQL parser.

[tv42]

If @foo is not even supposed to work right, https://docs.sqlc.dev/en/latest/howto/named_parameters.html needs to be updated to not recommend it as a shortcut.

If the sqlc.arg() syntax is too verbose for your taste, you can use the @ operator as a shortcut.