Thread

1. bug with distinct?

   Alfonso Peniche <alfonso@iteso.mx> — 2001-02-10T00:23:59Z

   I dont' know if this a bug or I am just out of my mind, but since it
   works with other RDBMS's I decided to ask, so here it goes:
   
   I am trying to do the following:
   
        SELECT distinct 'mod_type' ,currval('mytable_idmytable_seq') from
   mytable;
   
   and I get the message:
   
   ERROR:  Unable to identify an ordering operator '<' for type 'unknown'
    Use an explicit ordering operator or modify the query
   
   Thinking it could be because of the currval I tried the following:
   
        SELECT distinct 'mod_type', idmytable from mytable
   
   getting the same result.
   
   Am I doing something wrong? Is there a way to do this? Is this a bug?
   
   Thanx
   
   P.S. If someone is wondering what the heck I am trying to do.... I
   pretend to insert into a log table, the mod_type for 'mytable' (in this
   case insert) and the new inserted row for 'mytable'.
   
   Cheers
   
   
   

2. Re: bug with distinct?

   Peter Eisentraut <peter_e@gmx.net> — 2001-02-10T01:17:19Z

   Alfonso Peniche writes:
   
   >      SELECT distinct 'mod_type' ,currval('mytable_idmytable_seq') from
   > mytable;
   >
   > and I get the message:
   >
   > ERROR:  Unable to identify an ordering operator '<' for type 'unknown'
   >  Use an explicit ordering operator or modify the query
   
   Use 'mod_type'::text.
   
   -- 
   Peter Eisentraut      peter_e@gmx.net       http://yi.org/peter-e/
   
   
   

3. Re: bug with distinct?

   Tom Lane <tgl@sss.pgh.pa.us> — 2001-02-10T01:23:23Z

   Alfonso Peniche <alfonso@iteso.mx> writes:
   >      SELECT distinct 'mod_type' ,currval('mytable_idmytable_seq') from
   > mytable;
   > ERROR:  Unable to identify an ordering operator '<' for type 'unknown'
   >  Use an explicit ordering operator or modify the query
   
   You need to give the literal an explicit type, eg,
   
        SELECT distinct 'mod_type'::text, currval('mytable_idmytable_seq') from
        mytable;
   
   7.1 will default to assuming that you meant 'text' in this scenario,
   but older releases are pickier.
   
   			regards, tom lane
   
   

4. Re: bug with distinct?

   Alfonso Peniche <alfonso@iteso.mx> — 2001-02-10T17:11:14Z

   Quoting Tom Lane <tgl@sss.pgh.pa.us>:
   
   > Alfonso Peniche <alfonso@iteso.mx> writes:
   > >      SELECT distinct \'mod_type\' 
   ,currval(\'mytable_idmytable_seq\') from
   > > mytable;
   > > ERROR:  Unable to identify an ordering operator \'<\' 
   for type \'unknown\'
   > >  Use an explicit ordering operator or modify the 
   query
   >
   > You need to give the literal an explicit type, eg,
   >
   >      SELECT distinct \'mod_type\'::text, 
   currval(\'mytable_idmytable_seq\')
   > from
   >      mytable;
   >
   > 7.1 will default to assuming that you meant \'text\' in 
   this scenario,
   > but older releases are pickier.
   >
   > 			regards, tom lane
   > 
   Thanx, it woeks great now.
   
   Cheers
   
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