Re: Help :- testing if values are not in a table

select id from main
minus
select id from temp
/

Mike Kofal (mkofal_at_csn.net) wrote:
:> Andy MArr <andy_at_pindar.com> wrote:
 

:> >I've got a text file of ID type values which need to be compared agains
:> >the primary key of a main table with the same type of ID values.
 

:> >What I want to know is, whats the best(fast) way to check which values
:> >in the temporay table are NOT in the main table. Basically I want to
:> >list the values from the import file which are not in the database.
 

:> >I can only think of an individual select for each value or a WHERE NOT
:> >EXISTS type clause. Which would be the fastest ? , are there any other
:> >clever ways ? .
 

:> I have been using this trick for the past few years. I can't explain
:> WHY it is faster, but it works!
 

:> SELECT Temp.column
:> FROM Temp, Main
:> WHERE Temp.column = Main.column(+)
:> AND Main.column IS NULL

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