Be sure to check the validity of the data that you are importing! A program should not assume that everything in the incoming data stream is okay; in fact, it probably is not. (An import/export program, unlike most other programs, is considering every single one of the rows. Most programs only look at specific rows-of-interest and may never stumble upon those which contain errors of some kind. Thus, an import/export program is in a very favorable position to act as a data-integrity checker as well as a data mover.)