Re: Incorrect (?) escape of the $1

andrew(at)pillette(dot)com writes:
> Is there any magic sequence of quotes or backslashes that will get the following (simplified version) to do the obvious thing?
> CREATE FUNCTION doesnt_work(integer) RETURNS date LANGUAGE SQL AS
> 'SELECT (date ''epoch'' + interval '' $1 day'')::date ' STRICT IMMUTABLE;

> No variable interpolation is performed; the interval 1 day is always used.

You could probably make it work via string concatenation (||)
if you were absolutely intent on it, but far easier is to use the
number-times-interval operator:

CREATE FUNCTION does_work(integer) RETURNS date LANGUAGE SQL AS
'SELECT (date ''epoch'' + $1 * interval ''1 day'')::date'
STRICT IMMUTABLE;

regards, tom lane