Thread

1. Misleading Error Message

   Kristofer Munn <kmunn@munn.com> — 1999-05-16T04:10:12Z

   Hi all.  Was working tonight and ran into the following error.  Doing a
   union between two selects (to get around the lack of outer joins - hint
   hint), I was getting the error:
   
           ERROR: Each UNION clause must have the same number of columns
   
   Upon examining the SQL statement in question, I verified that it did,
   indeed, have the same number of columns.  After some fiddling, I found the
   actual problem was that I was doing an ORDER BY on a column which was not
   being included in the two select statements.  Unfortunately, the error
   message wasn't pointing at that.
   
   I'm not sure if this is just a simple change or implies other problems
   with the parser but I thought I'd toss it out onto the pile.
   
   Cya...
   
   - K
   
   Kristofer Munn * http://www.munn.com/~kmunn/ * ICQ# 352499 * AIM: KrMunn 
   
   
   
   

2. Re: [HACKERS] Misleading Error Message

   Bruce Momjian <maillist@candle.pha.pa.us> — 1999-05-16T05:25:59Z

   > Hi all.  Was working tonight and ran into the following error.  Doing a
   > union between two selects (to get around the lack of outer joins - hint
   > hint), I was getting the error:
   > 
   >         ERROR: Each UNION clause must have the same number of columns
   > 
   > Upon examining the SQL statement in question, I verified that it did,
   > indeed, have the same number of columns.  After some fiddling, I found the
   > actual problem was that I was doing an ORDER BY on a column which was not
   > being included in the two select statements.  Unfortunately, the error
   > message wasn't pointing at that.
   > 
   > I'm not sure if this is just a simple change or implies other problems
   > with the parser but I thought I'd toss it out onto the pile.
   
   Tom Lane discovered it a few days ago in relation to INSERT INTO table
   SELECT * FROM TABLE ORDER BY col1, and col1 was not in the select target
   list.  It shows an error.  We are looking at solutions.
   
   -- 
     Bruce Momjian                        |  http://www.op.net/~candle
     maillist@candle.pha.pa.us            |  (610) 853-3000
     +  If your life is a hard drive,     |  830 Blythe Avenue
     +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026
   
   

3. Re: [HACKERS] Misleading Error Message

   Jan Wieck <jwieck@debis.com> — 1999-05-17T08:27:26Z

   >
   > > Hi all.  Was working tonight and ran into the following error.  Doing a
   > > union between two selects (to get around the lack of outer joins - hint
   > > hint), I was getting the error:
   > >
   > >         ERROR: Each UNION clause must have the same number of columns
   > >
   > > Upon examining the SQL statement in question, I verified that it did,
   > > indeed, have the same number of columns.  After some fiddling, I found the
   > > actual problem was that I was doing an ORDER BY on a column which was not
   > > being included in the two select statements.  Unfortunately, the error
   > > message wasn't pointing at that.
   > >
   > > I'm not sure if this is just a simple change or implies other problems
   > > with the parser but I thought I'd toss it out onto the pile.
   >
   > Tom Lane discovered it a few days ago in relation to INSERT INTO table
   > SELECT * FROM TABLE ORDER BY col1, and col1 was not in the select target
   > list.  It shows an error.  We are looking at solutions.
   
       This  might  also  interfere with latest changes I did in the
       rewrite system. Parser and rewriter now add  junk  attributes
       to  the  targetlist.   I  think the problem is that the union
       code (where the check is done)  doesn't  recognize  that  the
       unequal  length of the targetlists is due to junk attributes.
   
   
   Jan
   
   --
   
   #======================================================================#
   # It's easier to get forgiveness for being wrong than for being right. #
   # Let's break this rule - forgive me.                                  #
   #======================================== jwieck@debis.com (Jan Wieck) #
   
   
   
   

4. Re: [HACKERS] Misleading Error Message

   Bruce Momjian <maillist@candle.pha.pa.us> — 1999-05-17T18:22:27Z

   > >
   > > > Hi all.  Was working tonight and ran into the following error.  Doing a
   > > > union between two selects (to get around the lack of outer joins - hint
   > > > hint), I was getting the error:
   > > >
   > > >         ERROR: Each UNION clause must have the same number of columns
   > > >
   > > > Upon examining the SQL statement in question, I verified that it did,
   > > > indeed, have the same number of columns.  After some fiddling, I found the
   > > > actual problem was that I was doing an ORDER BY on a column which was not
   > > > being included in the two select statements.  Unfortunately, the error
   > > > message wasn't pointing at that.
   > > >
   > > > I'm not sure if this is just a simple change or implies other problems
   > > > with the parser but I thought I'd toss it out onto the pile.
   > >
   > > Tom Lane discovered it a few days ago in relation to INSERT INTO table
   > > SELECT * FROM TABLE ORDER BY col1, and col1 was not in the select target
   > > list.  It shows an error.  We are looking at solutions.
   > 
   >     This  might  also  interfere with latest changes I did in the
   >     rewrite system. Parser and rewriter now add  junk  attributes
   >     to  the  targetlist.   I  think the problem is that the union
   >     code (where the check is done)  doesn't  recognize  that  the
   >     unequal  length of the targetlists is due to junk attributes.
   
   I have added code to the parser and rewrite checks to skip counting of
   resjunk nodes in checking for UNION length equality.  This should fix
   the problem.
   
   -- 
     Bruce Momjian                        |  http://www.op.net/~candle
     maillist@candle.pha.pa.us            |  (610) 853-3000
     +  If your life is a hard drive,     |  830 Blythe Avenue
     +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026
   
   

5. Re: [HACKERS] Misleading Error Message

   Bruce Momjian <maillist@candle.pha.pa.us> — 1999-05-17T18:23:00Z

   > Hi all.  Was working tonight and ran into the following error.  Doing a
   > union between two selects (to get around the lack of outer joins - hint
   > hint), I was getting the error:
   > 
   >         ERROR: Each UNION clause must have the same number of columns
   > 
   > Upon examining the SQL statement in question, I verified that it did,
   > indeed, have the same number of columns.  After some fiddling, I found the
   > actual problem was that I was doing an ORDER BY on a column which was not
   > being included in the two select statements.  Unfortunately, the error
   > message wasn't pointing at that.
   > 
   > I'm not sure if this is just a simple change or implies other problems
   > with the parser but I thought I'd toss it out onto the pile.
   
   
   This now fixed.
   
   -- 
     Bruce Momjian                        |  http://www.op.net/~candle
     maillist@candle.pha.pa.us            |  (610) 853-3000
     +  If your life is a hard drive,     |  830 Blythe Avenue
     +  Christ can be your backup.        |  Drexel Hill, Pennsylvania 19026