IZ0-051 – 11g SQL fundamentals
Here they have listed the exam topics –
Difference between 10g & 11g –
eg.,MERGE statement can include DELETE also, PIVOT / UNPIVOT functions are available for data transpose etc.,
Along with SQL fundamentals you should appear for IZ0-147 – PL/SQL fundamentals exam also.
Good news is OCP – Advanced PL/SQL Developer (IZ0-146) is available since Jan 2009 !
If you are even more interested you can do OCE – Oracle Certified Expert.