Re: [MonetDB-users] DB Corruption

24 Mar 2012

      Joseph,

since you did not specify your queries in more detail, I assume they are as
simple as
 (1)	select count(*) from ;
and
 (2)	select count(single_column) from ;

In that case, you could try the following sanity check:

 (3)	select count(*) from  where single_column is null;

and check whether that returns the difference between your counts.

If that indeed returns the difference between your global count(*) and
count(single_column), this would confirm the existence of NULL values, and
you'd need to invest which of the values in your CVS file have been
interpreted as NULL and why.

In case the result of queries (2) and (3) do not add up to the number
returned by query (1), you might want to check the output(s) of

	TRACE select count(*) from ;
	TRACE select count(single_column) from ;
	TRACE select count(*) from  where single_column is null;

(or have us check them, provided/once we find the time).

Stefan

On Sat, Mar 24, 2012 at 09:37:38AM -0600, Joseph Brower wrote:
...
There shouldn't be any nulls.  The records were all added by a "Copy
Into" command.  The files that we imported had no nulls in it at
all.
On 03/24/2012 01:57 AM, Sjoerd Mullender wrote:
...
On 2012-03-24 00:14, Joseph Brower wrote:
...
We were troubleshooting some odd results coming back from our database,
and found that it's missing some entries from a column.  This appears to
be causing some sort of offset.  Does anyone have any ideas on what can
be done to resolve it or what may have caused it?  Is there any
information we could send that would be helpful in troubleshooting this
or for a bug report?
If we do a count(*) and then a count('single_column') we are getting two
different results (when they should be indentical)
count (*) counts all rows, whereas count(single_column) only count
non-null values.  Are there any nulls in the single_column?
------------------------------------------------------------------------------
This SF email is sponsosred by:
Try Windows Azure free for 90 days Click Here
http://p.sf.net/sfu/sfd2d-msazure
_______________________________________________
MonetDB-users mailing list
MonetDB-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/monetdb-users

...
------------------------------------------------------------------------------
This SF email is sponsosred by:
Try Windows Azure free for 90 days Click Here 
http://p.sf.net/sfu/sfd2d-msazure
...
_______________________________________________
MonetDB-users mailing list
MonetDB-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/monetdb-users
-- 
| Stefan.Manegold @ CWI.nl | DB Architectures (INS1) |
| http://CWI.nl/~manegold/ | Science Park 123 (L321) |
| Tel.: +31 (0)20 592-4212 | 1098 XG Amsterdam  (NL) |

Re: [MonetDB-users] DB Corruption

Stefan Manegold