Certifications available for Application Developer:

Oracle PL/SQL Developer OCA
Oracle Forms Developer OCP
Internet Application Developer Rel.6i OCP

What is OCA (Oracle Certified Associate):
This exam is your first step to become an Oracle professional. You can take this exam for DBA as well as for developer.

What is OCP (Oracle Certified Professional):
This is an advanced certification that Oracle offers for a DBA. In order to get this certification, you should pass the OCP exam first and should complete a Hands-On Course with Oracle University.

What is OCM (Oracle Certified Master):
This is the most advanced exam for Oracle database administrators. Before you plan for this exam, you should have comprehensive and extensive experience on a wide variety of topics including installation, troubleshooting, backup and recovery and tuning.
The prerequisites require that candidates earn an Oracle Database 10g OCP stage requl and complete advanced-level coursework. The final stage requires that candidates demonstrate their skills through an intensive two-day hands-on practical examination.
 

OCA	OCP	OCM
Requirements for Oracle 10g	Requirements  for Oracle 10g	Requirements  for Oracle 10g
1Z0-042 Oracle Database 10g: Administration I	10g OCA 1Z0-043 Oracle Database 10g: Administration II Hands-On Course Requirement	10g OCP Two Advanced Hands-On Course Requirement Oracle Database 10g Certified Master Exam
Requirements for Oracle 9i	Requirements  for Oracle 9i	Requirements  for Oracle 9i
1Z0-007 Introduction to Oracle9i: SQL OR 1Z0-001 Introduction to Oracle: SQL PL/SQL 1Z0-031 Oracle9i Database: Fundamentals I	9i OCA 1Z0-032 Oracle9i Database: Fundamentals II 1Z0-033 Oracle9i Database: Performance Tuning Hands-On Course Requirement	Oracle9i DBA OCP Two Advanced Hands-On Course Oracle9i Certified Master Exam
Requirements for 9i Developer	Requirements for 9i Developer
1Z0-007 Introduction to Oracle9i: SQL OR 1Z0-001 Introduction to Oracle: SQL PL/SQL 1Z0-147 Program with PL/SQL	Oracle PL/SQL Developer OCA 1Z0-141 Oracle Forms: Build Internet applications