Fast Bulk Inserts into SQLite

Fast Bulk Inserts into SQLite
http://blog.quibb.org/2010/08/fast-bulk-inserts-into-sqlite/

Finding Duplicates with SQL
SELECT email, COUNT(email) AS NumOccurrences FROM users GROUP BY email HAVING ( COUNT(email) > 1 )

Finding rows that occur exactly once
SELECT email FROM users GROUP BY email HAVING ( COUNT(email) = 1 )