hi dear all

i have to need the idea for which one of the best databse

Thanks

Best at...? Oracle seems best when you need to work with a lot of xml. I've read that its user authentication isn't very secure, though. SQL Server is very good, especially the new one. MySQL only began to allow stored procedures at v 5, which are an essential part of a secure application, if that's what you're trying to build.

But to get an answer you can trust, you need to give some more information about what you want to do with the database. All of the competing engines have strengths and weaknesses.

Mysql is a good fail safe. I am happy with mysql5's newest features, I recommend it. Oracle is great, but mysql is free and I ahve never had an issue with it.

If you want to have most of oracle strong points in an open source way, take a look at postresSql.
http://www.postgresql.org/