Migration from Oracle to Teradata


Migration from Oracle to Teradata

Hi Guys

I am working on migration from Oracle to Teradata. I am facing few issues there. I would be glad if some one please clarify below questions.


Oracle has VARCHAR2 and NVARCHAR2 data type. I do not think Teradata has such data types. Even VARCHAR supports 2000 byte where VARCHAR2 is 4000 byte. So during migration to TD what suitable data type can be used?

Also during migration will it help if we change the character set to UNICODE in case the field length is too high (say >4000)?


There are few columns as BLOB and CLOB. Teradata has them. But I want to know, when to choose Inline transfer or Deferred transfer or Locator transfer of LOB from application to TD?

What difference they will possible make, I mean if I use AS DEFERRED, AS DEFERRED BY NAME , AS LOCATOR which one would be advantageous?

Please let me know the answers.




Re: Migration from Oracle to Teradata

Teradata has varchar data type.The maximum for latin is 64000 and unicode is 32000. As far as I remember NVARCHAR in oracle is good to convert to UNICODE. Please check.

It depends how you want to operate your LOB.In my opinion, it is better to use AS DEFERRED BY NAME. Please check the session for Locators.