bcp utility is a command line tool that ships with Microsoft SQL Server. It bulk copies data between SQL Azure (or SQL Server) and data file in user-specified format. bcp that ships with SQL Server 2008 R2 is fully supported by SQL Azure, and can be used to import large numbers of new rows into SQL Server tables or to export data out of tables into data files. Except when used with queryout option, bcp requires no knowledge of Transact-SQL. To import data into a table, you must either use a format file created for that table or understand structure of table and types of data that’re valid for its columns.
bcp isn’t a migration tool. It doesn’t extract or create any schema or format information from/in a data file or your table. This means, if you use bcp to back up data, make sure to create a schema or format file somewhere else to record schema of the table you’re backing up. bcp data files don’t include any schema or format information, so if a table or view is dropped and you don’t have format file, you may be unable to import data. bcp has several command line arguments.