Interview Q & A

Below are the Oracle Apps DBA Interview Questions which I have consolidated based on my real time experience.

I will update the answers as soon as possible.

Startup :

• Tell me about yourself
• What's your Day to Day activity
• Why are you looking for change?

Patching :

• adpatch process
• Hot patch? suppose the patch size is 15 MB ..can we apply hotpatch?
• How will you skip worker during patch ? 
• Database status while applying opatch?
• What are things you do to reduce patch timing ?
• opatch process?
• What are various options available with adpatch ?
• When you apply C driver patch does it require database to be Up and Why ?
• What is the difference between adpatch and opatch
• I am applying patch using adpatch,after that i come to know that i forgot to apply pre-requisite patch? what will you do?
• I am applying patch can I open another session in another node and run adpatch ?
• How to enable maintenance mode in R12 and What exactly happens when you put an Oracle Apps instance in maintenance mode ? 
• Before applying patch, I forgot to take count of invalid objects. now how to check what was count of invalids?

General :

• There are lot of DBC file under $FND_SECURE, How its determined that which dbc file to use from $FND_SECURE ?
• How to see the contents of application dbc file without login into putty
• What is the difference between Context file and Autoconfig?
• What will happen if ICM goes down?
• Can we delete ICM?
• cmclean ? when it is used?
• How many OC4J services are ther in R12?
• How to add additional node into existing configuration?
• What is difference between ICM, Standard Managers and CRM in Concurrent Manager ?
• What is the difference between SOCKET and SERVLET mode?
• Difference between 11i and R12
• How to retrieve context file in oracle apps/DB?
• Is there separate Report server in R12?
• What is the use of OPMN in Oracle apps?
• How to change apps password?
• What are the mandatory users in Oracle apps? applsyspub,applsys,apps
• Suppose my concurrent manager status is showing Inactive ? what is the reason ?
• How to know how many forms sessions are opened?
• How the connectivity happens from EBS application to Database?
• By mistake I deleted the scripts directory from apps and DB node? what to do now?

R12.2 :

• How to enable maintainance mode in R12.2?
• adop phases?

Cloning :

• Cloning process?
• How will troubleshoot Login page error that raised after cloning?

Database :

• How to recreate oracle inventory?
• How the scan listener works in 11g and how to configure it with EBS R12
• How to add additional RAC node in existing architecture?
• How to Add disk in ASM group?

Advanced Configuration:

• In PCP what will happen to running concurrent request if one pcp node failed where it was running
• How to create new user similar with SYSADMIN privs and responsibilities in EBS?
• How to change browser windows title at site level for Oracle applications home page (Note : if candidate says site name profile option then tell him it reflects only on forms session not on browser window, answer given below)
• How to check alert log without touching alert_SID.log or without login to putty filesystem.
• How to see the contents of application dbc file without login into putty?
• What will happen if you bounce apache service only?
• What will happen if you bounce oacore services?

Performance:

• How will you troubleshoot long running request?
• What is the difference between explain plan and execution plan?
• Can we get a execution plan after completion of SQL query?

Managerial Questions:

• You are working in a team..How will you prove that you are a good DBA?
• You are fully loaded due to work and one day you get 3-4 hours free time then what you will do in that free time related to work?

And few questions based on your projects like - Oracle EBS upgradation,PCP/Load Balancer/DMZ Configuration, Oracle Data Guard, RAC Configuration with EBS etc.

Best Luck :)