NAME
DS::Importer - component that retrieves data from outside DS and passes it down a processing chain.
DESCRIPTION
This is the base class of any component that is supposed to retrieve data from outside a processing chain and pass it on as rows. The name refers to a component that imports data into a chain.
SUPER CLASSES
METHODS
execute( $num_rows )
Will call fetch pass the results on by calling pass_row with the result, stopping after fetching $num_rows or passing on end of stream (whichever comes first).
fetch
This method is supposed to retrieve a row from the underlying data source and return it. Must return undef to indicate end of stream. Multiple calls after end of stream should still result in returning undef.
new( $class, $out_type, $target )
Constructor. Instantiates an object of class $class, returning the type $out_type, attaced to the target $target. Besides $class, any of the parameters can be left out.
INHERITED METHODS
Methods inherited from DS::Source:
SEE ALSO
DS::Importer, DS::Transformer, DS::Target.
AUTHOR
Written by Michael Zedeler.