Oracle dba interview questions by b g
1. how many memory layers are in the shared pool？
2. how do you find out from the rman catalog if a particular archive log has been backed-up？
3. how can you tell how much space is left on a given file system and how much space each of the file system’s subdirectories take-up？
4. define the sga and：
？ how you would configure sga for a mid-sized oltp environment？
？ what is involved in tuning the sga？
5. what is the cache hit ratio， what impact does it have on performance of an oracle database and what is involved in tuning it？
6. other than making use of the statspack utility， what would you check when you are monitoring or running a health check on an oracle 8i or 9i database？
7. how do you tell what your machine name is and what is its ip address？
8. how would you go about verifying the network name that the local_listener is currently using？
9. you have 4 instances running on the same unix box. how can you determine which shared memory and semaphores are associated with which instance？
10. what view（s） do you use to associate a user’s sqlplus session with his o/s process？
11. what is the recommended interval at which to run statspack snapshots， and why？
12. what spfile/init.ora file parameter exists to force the cbo to make the execution path of a given statement use an index， even if the index scan may appear to be calculated as more costly？
13. assuming today is monday， how would you use the dbms_job package to schedule the execution of a given procedure owned by scott to start wednesday at 9am and to run subsequently every other day at 2am.
14. how would you edit your crontab to schedule the running of /test/test.sh to run every other day at 2pm？
15. what do the 9i dbms_standard.sql_txt（） and dbms_standard.sql_text（） procedures do？
16. in which dictionary table or view would you look to determine at which time a snapshot or mview last successfully refreshed？
17. how would you best determine why your mview couldn’t fast refresh？
18. how does propagation differ between advanced replication and snapshot replication （readonly）？
19. which dictionary view（s） would you first look at to understand or get a high-level idea of a given advanced replication environment？
20. how would you begin to troubleshoot an ora-3113 error？
21. which dictionary tables and/or views would you look at to diagnose a locking issue？
22. an automatic job running via dbms_job has failed. knowing only that "it’s failed"， how do you approach troubleshooting this issue？
23. how would you extract ddl of a table without using a gui tool？
24. you’re getting high "busy buffer waits" - how can you find what’s causing it？
25. what query tells you how much space a tablespace named "test" is taking up， and how much space is remaining？
