Re: [PATCH] pg_sleep(interval)

On Fri, Aug 16, 2013 at 2:57 PM, Greg Stark <stark(at)mit(dot)edu> wrote:
> Except there are no data types that can be cast to both double and
> interval currently.

That, unfortunately, is not sufficient to avoid a problem.

rhaas=# create or replace function foo(double precision) returns
double precision as $$select $1$$ language sql;
CREATE FUNCTION
rhaas=# create or replace function foo(interval) returns interval as
$$select $1$$ language sql;
CREATE FUNCTION
rhaas=# select foo('123');
ERROR: function foo(unknown) is not unique
LINE 1: select foo('123');
^
HINT: Could not choose a best candidate function. You might need to
add explicit type casts.
rhaas=#

--
Robert Haas
EnterpriseDB: http://www.enterprisedb.com
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