Executes a Pig Latin script up to and including indicated alias. That is, if a user does:
PigServer server = new PigServer(); server.registerQuery("A = load 'foo';"); server.registerQuery("B = filter A by $0 > 0;"); server.registerQuery("C = order B by $1;");
Then
server.openIterator("B");
filtered but unsorted data will be returned. If instead a user does
server.openIterator("C");
filtered and sorted data will be returned.
@param id Alias to open iterator for
@return iterator of tuples returned from the script
@throws IOException