Oracle DBA Interview questions and Answers

Are you a Database Administrator? Need to update DBA technical knowledge or need to prepare for a job interview? Check out this collection of Oracle DBA Interview questions and Answers...
Oracle DBA Interview questions and Answers

• What is different between TRUNCATE and DELETE?
• What is the maximum buffer size that can be specified using the DBMS_OUTPUT.ENABLE function?
• Can you use a commit statement within a database trigger?
• What is an UTL_FILE? What are different procedures and functions associated with it?
• What are between database triggers and form triggers?
• What is OCI. What are its uses?
• What are ORACLE PRECOMPILERS?
• What is syntax for dropping a procedure and a function? Are these operations possible?
• How to check if application 11i System is Autoconfig enabled ?
• How to check if Oracle application 11i System is Rapid Clone enabled ?
• Whats is difference between two env files in <CONTEXT>.env and APPS<CONTEXT>.env under $APPL_TOP ?
• What is main concurrent Manager types.
• What is US directory in $AD_TOP or under various product TOP's .
• Where is Concurrent Manager log file location.
• Where would I find .rf9 file, and what it dose ?
• Where is appsweb.cfg or appsweb_$CONTEXT.cfg stored and why its used ?
• What is Multi Node System ?
• Can a function take OUT parameters. If not why?
• Can the default values be assigned to actual parameters?
• What is difference between a formal and an actual parameter?
• What are different modes of parameters used in functions and procedures?
• What is difference between procedure and function.
• Can cursor variables be stored in PL/SQL tables. If answer is yes, explain how? If not why?
• Can you clone from multi node system to single node system and vice versa ?
• Does rapid clone takes care of Updating Global oraInventory or you have to register manually in Global OraInventory after clone ?
• What is .dbc file , where its stored , whats use of .dbc file ?
• What are things you do to reduce patch timing ?
• How you put Applications 11i in Maintenance mode ?
• Can you apply patch without putting Applications 11i in Maintenance mode ?
• What are various options available with adpatch ?
• ADIDENT UTILITY is used for what ?
• How do you pass cursor variables in PL/SQL?
• How do you open and close a cursor variable. Why it is required?
• What should be the return type for a cursor variable. Can we use a scalar data type as return type?
• What is use of a cursor variable? How it is defined?
• What WHERE CURRENT OF clause does in a cursor?
• What is different between NO DATA FOUND and %NOTFOUND
• What is a cursor for loop?
• What is iAS Patch ?
• If we run autoconfig which files will get effected ?
• What is difference between .xml file and AutoConfig ?
• What is .lgi files ?
• How will you skip worker during patch ?
• Which two tables created at start of application Patch and drops at end of Patch ?
• How to compile an Oracle Reports file ?
• What is difference between AD_BUGS and AD_APPLID_PATCHES ?
• What is ADSPLICE UTILITY ?
• How can you licence a product after installation ?
• What is MRC ? What you do as application DBA for MRC ?
• What is access_log in apache , what entries are recored in access_log ? Where is default location of this file ?
• Where is Jserv configuration files stored ?
• Where is applications start/stop scripts stored ?
• What are main configuration files in Web Server (Apache) ?
• Can C driver in application patch create Invalid Object in database ?
• What is dev60cgi and f60cgi ?
• Why does a worker fails in Oracle Apps Patch and few scenarios in which it failed for you ?
• What is difference between mod_osso and mod_ose in Oracle HTTP Server ?
• What is difference between COMPILE_ALL=SPECIAL and COMPILE=ALL while compiling Forms ?
• What is GSM in Oracle application E-Business Suite ?
• What is FNDSM ?
• What are cursor attributes?
• What is difference between an implicit and an explicit cursor.
• What is a cursor?
• What is the purpose of a cluster?
• How do you find the number of rows in a Table ?
• What is a pseudo column. Give some examples?
• Whats is location of access_log file ?
• What is your Oracle application 11i Webserver Version and how to find it ?
• What is Location of Jserv configuration files ?
• What is plssql/database cache ?
• Where is DATABASE/PLSSQL cache stored ?
• What is *.DBC file and whats is location of DBC file ?
• What is content of DBC file and why its important ?
• What are few profile options which you update after cloning ?
• How to retrieve SYSADMIN password ?
• What is TWO_TASK in Oracle Database ?
• What is GWYUID ?
• Where GWYUID defined and what is its used in Oracle Applications ?
• If APPS_MRC schema is not used in 11.5.10 and higher then How MRC is working ?
• When you apply C driver patch does it require database to be Up and Why ?
• How you will avoid your query from using indexes?
• What is a OUTER JOIN?
• Which is more faster - IN or EXISTS?
• When do you use WHERE clause and when do you use HAVING clause?
• There is a % sign in one field of a column. What will be the query to find it?
• Where will you find forms configuration details apart from xml file ?
• What is forms server executable Name ?
• What are different modes of forms in which you can start Forms Server and which one is default ?
• How you will start Discoverer in Oracle Applications 11i ?
• How many ORACLE HOME are Oracle Applications and whats significance of each ?
• Where is HTML Cache stored in Oracle Applications Server ?
• Where is plssql cache stored in Oracle Applications ?
• What happens if you don't give cache size while defining Concurrent Manager ?
• There are lot of DBC file under $FND_SECURE, How its determined that which dbc file to use from $FND_SECURE ?
• What is RRA/FNDFS ?
• What is PCP is Oracle Applications 11i ?
• Why I need two Concurrent Processing Nodes or in what scenarios PCP is Used ?
• Output and Logfiles for requests executed on source Instance not working on cloned Instance
• How to confirm if Report Server is Up and Running ?
• What is difference between ICM, Standard Managers and CRM in Concurrent Manager ?
• What is difference between SUBSTR and INSTR?
• Which data type is used for storing graphics and images?
• What is difference between SQL and SQL*PLUS?
• What is difference between UNIQUE and PRIMARY KEY constraints?
• What is difference between Rename and Alias?
• What are various joins used while writing SUBQUERIES?
• What is use of Applications listener ?
• How to start Applications listener ?
• How to confirm if Apps Listener is Up and Running ?
• What is Web Listener ?
• How will you find Invalid Objects in database ?
• How to compile Invalid Objects in database ?
• How to compile JSP in Oracle Applications ?
• What is difference between ADPATCH and OPATCH ?
• Can you use both ADPATCH and OPATCH in application ?