How to COALESCE a timestamp column? - postgresql

Question

In PostgreSQL 9.3 I have the following table with 2 timestamps:
create table pref_users (
id varchar(32) primary key,
first_name varchar(64) not null,
last_name varchar(64),
female boolean,
avatar varchar(128),
city varchar(64),
mobile varchar(64),
login timestamp default current_timestamp,
logout timestamp,
last_ip inet,
vip timestamp, /* XXX can be NULL */
grand timestamp, /* XXX can be NULL */
mail varchar(256),
green integer,
red integer,
medals integer not null default 0
);
The timestamps vip and grand indicate if the users of my game have paid for certain privilleges - until those dates.
When a user connects to my game server, I call the following procedure with OUT parameters:
create or replace function pref_get_user_info(
IN _id varchar,
OUT is_banned boolean,
OUT is_grand boolean,
OUT is_vip boolean,
OUT rep integer
) as $BODY$
begin
is_banned := exists(select 1 from pref_ban where id=_id);
if is_banned then
return;
end if;
select
grand > current_timestamp,
vip > current_timestamp,
into is_grand is_vip
from pref_users where id=_id;
if is_grand or is_vip then
return;
end if;
select
count(nullif(nice, false)) -
count(nullif(nice, true))
into rep
from pref_rep where id=_id;
end;
$BODY$ language plpgsql;
This does work well, but sometimes delivers NULL values to my game daemon (to a Perl script):
# select * from pref_get_user_info('OK674418426646');
is_banned | is_grand | is_vip | rep
-----------+----------+--------+-----
f | | | 126
(1 row)
I don't need a NULL though (and it prints a warning in my Perl script) - I just need a "true" or "false" values there.
So I have tried:
select
coalesce(grand, 0) > current_timestamp,
coalesce(vip, 0) > current_timestamp,
into is_grand is_vip
from pref_users where id=_id;
But this gives me error:
# select * from pref_get_user_info('OK674418426646');
ERROR: COALESCE types timestamp without time zone and integer cannot be matched
LINE 2: coalesce(grand, 0) > current_timesta...
^
QUERY: select
coalesce(grand, 0) > current_timestamp,
coalesce(vip, 0) > current_timestamp,
is_vip
from pref_users where id=_id
CONTEXT: PL/pgSQL function pref_get_user_info(character varying) line 9 at SQL statement
So I wonder what to do here please?
Do I really have to
select
coalesce(grand, current_timestamp - interval '1 day') > current_timestamp,
coalesce(vip, current_timestamp - interval '1 day') > current_timestamp,
into is_grand is_vip
from pref_users where id=_id;
or is there maybe a nicer way (like maybe "epoch start" or "yesterday")?
UPDATE:
As suggested by Clodoaldo Neto (thanks!) I've tried:
select
coalesce(grand > current_timestamp, false),
coalesce(vip > current_timestamp, false),
into is_grand is_vip
from pref_users where id=_id;
but is_vip is NULL when vip is NULL:
# select * from pref_get_user_info('OK674418426646');
is_banned | is_grand | is_vip | rep
-----------+----------+--------+-----
f | t | |
(1 row)
And when I try either of the following I get syntax error:
select
coalesce(grand > current_timestamp, false),
coalesce(vip > current_timestamp, false),
into is_grand, is_vip
from pref_users where id=_id;
select
coalesce(grand > current_timestamp, false),
coalesce(vip > current_timestamp, false),
into (is_grand, is_vip)
from pref_users where id=_id;
How can I SELECT into 2 variables at once here?

Answer 1

If you want a boolean:
coalesce(grand > current_timestamp, false)
If you need 0 or 1:
coalesce((grand > current_timestamp)::integer, 0)
In your updated question you have an extra comma between the select list and the into clause
coalesce(vip > current_timestamp, false),
into is_grand, is_vip
Take it out
coalesce(vip > current_timestamp, false)
into is_grand, is_vip