It's just a regular Union :-) http://avro.apache.org/docs/1.7.6/spec.html#Unions
Regards, Mike On Jul 23, 2014 1:22 AM, "Echo" <echo...@gmail.com> wrote: > Thanks Mike, it sounds make sense, is there any doc I can read about union > schema? > > On Jul 22, 2014, at 2:32 PM, Michael Pigott < > mpigott.subscripti...@gmail.com> wrote: > > Echo, > Just to make sure I understand you correctly - do you have a file with > multiple Avro datums in it, each one following a separate schema? And are > all of these schemas unioned together in a file-level "master schema?" (As > far as I know, Avro file readers and writers only support one schema per > file, so this is the only way your question makes sense to me.) > If that's the case, then you can get the file's "master schema" and > determine what all of the different types are: > > List<Schema> allTypes = masterSchema.getTypes(); // Assumes masterSchema > is of Type.UNION > > Then when you read each Avro datum in the file, you can check which of the > schemas it conforms to, and write a new file with just that sub-schema and > the one datum in it. > > Does that make sense? > Mike > > > On Tue, Jul 22, 2014 at 3:22 PM, Lewis John Mcgibbney < > lewis.mcgibb...@gmail.com> wrote: > >> For the purpose of others on this list, can ytou please provide an >> example of your schema? >> Thanks >> Lewis >> >> >> On Tue, Jul 22, 2014 at 12:06 PM, Echo Li <echo...@gmail.com> wrote: >> >>> Hello, >>> >>> I'm new here, hope I can get help from you guys. Basically I have an >>> avro file with union/many schemas and mixed records. I will need to split >>> it to many avro file, one schema per file. All the stuff I've been reading >>> is about serializing and deserializing avro file with one schema, which is >>> pretty straightforward, but in my case I have no clue, any ideas? >>> >> >> >> >> -- >> *Lewis* >> > >
