The problem I am working on requires me to retrieve a recordset from a databse with about 14000 records. Then I retrieve another recordset from a database that may have around 14000 records. (The numbers are arbitrary and may never be the same)

Once I have these 2 recordsets I need to iterate over one of them. For each record in the first recordset I need to see if there are any records in the second recordset with the same Serial Number and if so then do some processing with the corresponding data.

I was accomplishing this initially using collections rather than recordsets for indexing. However this turned out to be WAY too slow so I decided to just stick with recordsets and figure out the filter property.

For each record in the first recordset I am setting the filter property of the second recordset to all records that have the same serial number as the current record in the first recordset. This appears to be working though it takes almost 3-4 full seconds to filter. Since I am iterating over every record in the first recordset (again 14000+ records) this will take almost half a day to run!

Is there a better way to accomplish such a task?
What factors determine how long a filter takes to process?

-K