BCP, short for bulk copy program is a command-line variation of bulk operations. BCP differs from BULK INSERT in that it is command-line
executed and can import or export data. It uses many of the same options as BULK INSERT. The basic syntax is as follows:
BCP destination table direction datafile options
For the destination, use the server name along with the complete three-part name (server and database.schema.object). For a complete listing of the syntax, just type BCP at the command prompt. Because this is an external program, it needs authorization to connect to SQL Server. You have two options: Use the -P password option and hard-code your password into the batch file script, or omit the -P, in which case it will prompt for a password. Neither is a very good option. You can also use integrated security, which is usually considered the best practice.
For straightforward ETL operations, I prefer using T-SQL and BULK INSERT. For complex ETL loads, Integration Services is great. To be frank, I have little use for automating ETL processes using DOS batch scripts and BCP, although Powershell may make a believer of me yet.