src/docs/user/controlling-input-format.txt

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Controlling the Input Format
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

include::input-formatting.txt[]

The following arguments allow you to control the input format of
records:

include::input-formatting-args.txt[]

If you have already imported data into HDFS in a text-based
representation and want to change the delimiters being used, you
should regenerate the class via `sqoop \--generate-only`, specifying
the new delimiters with +\--fields-terminated-by+, etc., and the old
delimiters with +\--input-fields-terminated-by+, etc. Then run a
MapReduce job where your mapper creates an instance of your record
class, uses its +parse()+ method to read the fields using the old
delimiters, and emits a new +Text+ output value via the record's
+toString()+ method, which will use the new delimiters. You'll then
want to regenerate the class another time without the
+\--input-fields-terminated-by+ specified so that the new delimiters
are used for both input and output.