table download upload

I have to move all the rows of table a into table b(append). They both reside on two different servers. I need to perform some edits on the data in table a. More precisely, an entire column needs to be changed. Table A rows need to be deleted after the completion. Could you please tell me a fast and efficient method? Thank you.

a fast and efficient method would be to read the documentation about distributed databases and database links. You might then followup with a reading of the SQL manual and maybe the Concepts manual as well...

Or, you might choose to read the SQL*Plus manual about the COPY command.