All good points, but why even worry about it? Grab MySQL, take 20 min and install it, use the DBI, and then your system will be good up to about 1-2 million records (Use Postgres for more) _plus_ no locking worries about your data. It'll take the same amount to time to install the latest Berkley DBM. Your talking about expansion - and using a web server to handle access to your data , and dont forget about generating reports based on the nature of your data, adding and deleting records, type safety etc. If your are unfamiliar with SQL, the time to get aquainted is now, as opposed to when there are 200 000 records in your dbm.
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