Hello, is there one knows where I can find a database design for a full finance System ?

Sure. At a bank.

If you are really interested you could take a look at SAP or Oracle's financial apps - although they generally don't publicise the documentation for their data models.

You are unlikely to find them useful. The only people who develop such systems these days are the software vendors. Everyone else just buys the software.

Open source has a PERL based package called SqlLedger. Its introductory page will list nearly 20 fucntions and scenarios. Could be a good statring point.

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