Re: Concurrent accesses - Mac (or PC) - 5 users

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Disclaimer: I've never used SQLite over a network file system.

Dominique wrote:
> Hello All,
> 
> I swiftly went through the site and the wiki but I'd like to get
> your opinion before going further.
> 
> - I want to set up a small database with less 1500 clients and
>   related data, 5 users.
> - All 5 users will get on their machine a software I am writing
>   in python (+wxpython) to access and manage the database.
> - Machines for users are Mac (OS X).
> - There are small but NOT NONE chances that several users would try
>   modifying the same clients on the database at the same moment.
> - The database file would be owned by one of the machine (they are not
>   overloaded...) and accessed through a small network.
> Or possibly if necessary on a dedicated Mac or PC.
> 
> I have read that there may be problems due to file-locking system
> weaknesses / failures.

SQLite FAQ #5 (http://www.sqlite.org/faq.html) says that using SQLite over
NFS *may* be problematic, depending on the degree of bugginess of the NFS
implementation.

> Questions:
> 
> 1) What do you advise me to do ?
> Can I contemplate using sqlite for such an application.

SQLite *might* work, but I'd recommend you using something that *will*
work, i. e. a classic client-server database system.

> 2) Is there an unacceptable probability that we would get problems with
> simultaneous acesses ? (for me, once a year with an easy fix process is Ok.
> Once per day is not....)

I believe that if you decide to use SQLite, you will invest a few hours
testing the setup at least if concurrent write access works ok. This time
seems better invested into setting up a "real" database server.

> 3) In case of problems, what happens then ?
> Is the database file irremediably lost ???
> Or is there an  easy repair process ?

I don't really know :-/

> 4) [...]
> 
> 5) Or would you advise me to go for something else (Postgresql, mysql...)?

That's what I'd recommend.

> 6) Would the answers be the same with users and database working with pcs.

Yes.

- -- Gerhard
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