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    <p>"Users can be able to edit their own records" What does it mean for you? A database in which records are not editable, that is a Read/Only database, is not very common.</p> <p>You'll have to think about the general architecture of your software. You just don't select a database like a new car. I'd suggest that you won't be focused on the database choice, but take a look at the whole picture.</p> <p>Here are some advices:</p> <ol> <li><p>Separate your database storage, the User Interface, and your software logic. This is called 3-Tier, and is definitively a good idea if you're starting a new project in 2010. It will save you a lot of time in the future. We use such an architecture in our <a href="http://blog.synopse.info/category/Open-Source-Projects/SQLite3-Framework" rel="nofollow noreferrer">http://blog.synopse.info/category/Open-Source-Projects/SQLite3-Framework</a></p></li> <li><p>Use a database connection which is not fixed to one database engine. Delphi comes with DBX, and there are free or not so expensive alternatives around. See <a href="http://edn.embarcadero.com/article/39500" rel="nofollow noreferrer">http://edn.embarcadero.com/article/39500</a> for dbx and <a href="http://www.torry.net/pages.php?id=552" rel="nofollow noreferrer">http://www.torry.net/pages.php?id=552</a> for alternatives</p></li> <li><p>Think about the future: try to guess what will be the features of your application after some time, and try to be ready to implement them in your today's architecture choices.</p></li> </ol> <p>In all cases, you're right asking for advice and feedback. The time you're spending now before coding will spare your time during future maintenance.</p> <p>For example, if one of your request is that "All records will be string", with some BLOB, your database size won't never be bigger than a few GB. SQLite3 could be enough for you, and there is no size limitation in the TEXT fields in this database. </p>
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    1. POBest Database selection for Client/Server Application (Multiuser) with Delphi?
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    1. USA.Bouchez
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    1. COSQLite locking mechanism is not the best for high concurrency - writers lock the whole database. Even before deciding how to code your application, you have to understand how your application needs to use your database - and then select a database that works best in that scenario (as long as the database is not "given" and not changeable) within your budget.
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    2. COSQLite locking has been upgraded a lot, with the new WAL journaling system, included since version 3.7. Concurrency is now very good for reading, but writers still lock the whole DB, but it's very fast in practice, since most DB usage scenarii do much more reading than writing. I'm not sure that Alper knows his exact needs about DB and storage. In all cases, it could be a good idea to look after the ORM approach for a new software. There are multiple threads about Delphi ORM in stackoverflow.
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    3. COUpdating and deleting is writing too. Everything depends on the database usage profile. Whatever approach one uses to access the DB it has to face concurrency issues. Unless the middle-tier serializes everything <g>
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