Cursor.FindSingleValue

[Ivan Smahin]

Hello Thomas,

Monday, December 28, 2009, 10:23:11 PM, you wrote:


 >>     and then in cursor you can do binary search by that field values.

> what is "binary search by that field value"  ?


The best and most natural way is to query only records you really need
in. It looks like you do something like "select * from table" and than
you are trying to apply another search criteria to the query result.

But  you  should  do  something like "select f1, f2 from t1 where f3 =
'value'"  or  something  like  this instead -  I mean you should express your
search criteria inside the query.

Another  way  is  creating  some temporary table as a query result.
It would be probably helpful in case of long running queries
with complex search criteria. So later you could search a records in
that temporary table as you are trying to do with cursor.

One more note. Such problems may be result of poor database design.
One of the popular example is denormalization... In short ...
Assume you are developing some db schema for address book and you
decide  to keep all properties in different tables linked all together
with some sort of link. So you will get something like People table,
Address  table  (linked  to  People  table)  and  so on... Seems to be
correct...  But  finally you see that the only query you will run is -
get all properties for all men/women.

In our case it would be something like
SELECT * FROM tblPerson JOIN tblAddresses JOIN tblPhones JOIN....
WHERE  fldGender = ...

But  in  this  case probably it would be better to have a single table
with all that properties - yes it would be some repeatable records but
your query might be running faster than n-join-query...

To be more specific you should describe your needs more detailed.

-- 
Best regards,
Ivan Smahin 
Senior Software Engineer
Paradigma Software, Inc
Valentina - The Ultra-Fast Database
http://www.valentina-db.com