Re: [HACKERS] Re: [QUESTIONS] MySQL benchmark page - Mailing list pgsql-hackers

On Mon, 16 Mar 1998, Thomas G. Lockhart wrote:

> > > first the concatenation with ||
> > > the test is select 'abc' || 'def'
> > > and that's not working in postgres. In other db's it's working.
> >
> > Looks like we have a type problem here.  That type system again.
>
> "that type system" is A Good Thing(tm).
>
> tgl=> select 'abc' || 'def';
> ERROR:  There is more than one operator '||'
>  for types 'unknown' and 'unknown'
>  You will have to retype this query using an explicit cast

This sentence doesn't work on MySQL too, take a look:

mysql> select 'abc' || 'def';
1 row in set (0.00 sec)
+----------------+
| 'abc' || 'def' |
+----------------+
|              0 |
+----------------+
The result should be 'abcdef' not 0 !!