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ORACLE EXP/IMP &DATAPUMP INTERVIEW QUESTIONS

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  1. How can i make export faster?
    1. By using DIRECT=Y and BUFFER parameters
  1. Which process is responsible for writing data into dumpfile?
    1. Which process is responsible for writing data into dumpfile?
  1. What is the use of consistent=y parameter in export?
    1. It will take consistent values while taking export of a table
  1. What the parameter COMPRESS will do during export?
    1. During import, It will put entire data in a single extent
  1. How can we confirm that export dumpfile is valid?
    1. By using SHOW=Y option during import
  1. If you got a dumpfile to import and don’t know the fromuser, how you will get  that information?
    1. We can check that in export log file. If not, we can do import with SHOW=Y which generates a log file. Fromuser will be there in that log file
  1. What precautions you will take t perform a schema exp/imp between a prod and  dev database?
    1. We need to check if already user existing in dev database
    2. If so, drop the user (take DDL and permissions info well before) or drop all the objects
  1. What are the advantages of datapump over exp/imp?
    1. It is faster than exp/imp as we can use parallel and other options
    2. List all other from your class notes
  1. Can we import a 11g dumpfile into 10g database using datapump? If so, is it also  possible between 10g and 9i?
    1. Yes we can import from 11g to 10g using VERSION option. This is not possible between 10g and 9i as datapump is not there in 9i
  1. We exported a table and imported into dev database. After checking we found  table is residing in SYSTEM tablespace. What could be the reason?
    1. The user is having RESOURCE role assigned. If we assign RESOURCE role, it will give some quota on SYSTEM tablespace which is dangerous
  1. What you will do when export is running slow?
    1. We need to skip taking export of indexes, use BUFFER and DIRECT parameters
  1. Import process is running slow, what can you do now to make it faster?
    1. We can skip importing indexes as it is the most time taking job during import
  1. You are observing undo tablespace error during import, how you will avoid it?
    1. We can use COMMIT=Y option

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