Re: SQL Bug

On Thu, Oct 6, 2016 at 12:22 PM, Bujji Babu <bujji(dot)babu(at)heales(dot)com> wrote:
>
> Version string: PostgreSQL 9.5.4 on x86_64-pc-linux-gnu, compiled by
gcc (GCC) 4.8.5 20150623 (Red Hat 4.8.5-4), 64-bit
>
> Please let me know if anyone knows how to fix this. below query works
fine in version 9.4.
>
>
> select * from connectby('emp','empid','mgrid','1',0)
> AS t(keyid text, parent_keyid text, level int);
>
>
>
> ERROR: invalid return type DETAIL: SQL key field type text does not match
return key field type integer. ********** Error ********** ERROR: invalid
return type SQL state: 42804 Detail: SQL key field type text does not match
return key field type integer.
>
> CREATE TABLE public.emp
> (
> empid integer NOT NULL,
> name text,
> mgrid integer,
> CONSTRAINT emp_pkey PRIMARY KEY (empid)
> )

Hello,

This is not a bug.

From the documentation at
https://www.postgresql.org/docs/9.5/static/tablefunc.html

> The first two output columns are used for the current row's key and its
parent row's key; they must match the type of the table's key field.

So, you need to change the type of the first two returned columns to int:

=# select * from connectby('emp','empid','mgrid','1',0) AS t(keyid int,
parent_keyid int, level int);
keyid | parent_keyid | level
-------+--------------+-------
1 | | 0
2 | 1 | 1
4 | 2 | 2
5 | 2 | 2
3 | 1 | 1
(5 rows)

--
Alex