The Best Way to Check a Database.

Hello All,
I'm working on an app. where I'll retrieve upwards of 1 million items.
For each retrieval, I have to make sure that the item was not previously retrieved and stored. That means on the 1millionth item, I have to test the previous 999,999 items . If a match is found, I would ignore it. Other wise I would add it to the store.
I thought about storing all items in a simple hashtable. But 1 million items in a hashtable probably wouldn't be supported on a standard 128MB pc.
So my only other option seems to be database.
But the time required to retrieve and compare to the database seems like it would take forever.
My best guess would be to retrieve say 3000 items then do all my tests at that time and store. Clear the memory and repeat. Is that the strategy you guys would try ?
Does that seem doable -- i'll be using a standard jdbc-odbc bridge by the way
stev
Then I'm going to dump it into a database (MSAccess 2000) using the batch method -if the addBatch method is supported by

If you create your database table to have an index which requires unique values, then an insert of a duplicate will throw an exception. I don't know whether addBatch will be practical here -- it might throw the exception and not add the rest of the batch, but then again it might not. Of course, adding 1 million items is going to take some time, but the other advantage of the database is that the data is permanently stored in a form that's easy to access in a variety of ways.

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