Which Database?

Dear Group,

I've recently finished training as a C programmer and am looking to enhance my skill set by adding a RDBMS. I have already started studying ANSI SQL, from which I will hopefully have a good starting point to go on to a Commercial RDBMS product i.e.. Oracle, Sybase, Informix etc.

However, which one do I use? I code mainly in UNIX(Solaris) if that narrows the selection. I guess what I'm really asking is, what is the most widely used and accepted Commercial Package?, or is it just a case of "each to his own".

If anybody could point me to any websites which compare Commercial Databases or just discuss the different versions, strengths and weaknesses, that would be great. I've already checked out the Macmillan site for the "SQL in 21 Days" book which was suggested in an earlier thread but it wasn't really what I was looking for.

Many Thanks

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