Re[2]: AW: [HACKERS] isnull() or is it?t

If it is interesting to someone, we can partially emulate COALESCE
right now as:

create function coalesce(integer) returns integer as
'declare       nonullo alias for $1;
begin    if nonullo then       return nonullo;    else       return 0;    end if;end;
' language 'plpgsql';
CREATE

select *,coalesce(comm) from emp where comm is null;

ename|empno|job       |  hiredate|sal      |comm|deptno|level| mgr|coalesce
-----+-----+----------+----------+---------+----+------+-----+----+--------
BLAKE| 7698|MANAGER   |1981-05-01|$2,850.00|    |    30|    3|7782|       0
JONES| 7900|CLERK     |1981-12-03|$950.00  |    |    30|    2|7782|       0
CLARK| 7844|SALESMAN  |1981-09-08|$1,500.00|    |    10|    2|7839|       0
(3 rows)

-Jose'-

>> > > With SyBase, IsNull(X,Y) returns X if X is not null, and Y
>> > > if X is null.
>> > 
>> > Which is identical in behavior to the SQL92-defined function
>> > COALESCE(X,Y) (IsNull() is not in the standard). This is now in the
>> > Postgres development tree, to be available in the next release. Should
>> > we also have the less capable IsNull() available too? COALESCE() has the
>> > nice feature that it takes an unlimited number of arguments, returning
>> > the first non-null result.
>> 
>> Oh, NVL and isnull are not standard?  Then let's just use coalesce.  I
>> will remove them from the TODO list.

VV> Surprises me too.  I was under the (incorrect) impression that isnull
VV> was standard.