What is the fastest method to migrate large tables from Oracle to SQL Server?
BCP would be a good choice. Export your data to a text file and then import it. To do this follow these steps:


Create your new table in sql server
Insert 1 row of data into this new table
Use BCP to get an export from this table containing this 1 row
This is necessary so that you can create an export from Oracle that matches this. Example:


  bcp yourdatabase.dbo.yourtable out yourtable.dat -T -c

Check the format in yourtable.dat
Generate an output file from Oracle that matches the format of yourtable.dat
Use bcp again to load the data file that was created by oracle into sql server. Example:


  bcp yourdatabase.dbo.yourtable in yourtable.dat -T -c



Try with 5000 rows. Get it working properly then time it and load. BCP will be fast.