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Avro >> mail # dev >> A case for adding revision field to Avro schema


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RE: A case for adding revision field to Avro schema
Thanks Philip for your crisp description of what happens with Thrift and PB.
I had assumed that the community knows the difference between those systems
and Avro. your description should help those who don't know and be refresher
for those who know.

> What happens if the application doesn't recognize the branch number?  If
> you're a client of a get_person(id) call, and you were written when
> Person_v1 was the only one in existence, Avro, today, would do just fine
at
> projecting Person_v2 down into Person_v1 for you.  That's because your
> reader schema would be v1, and you'd read some data written with v2, and
> those are compatible.  If you have a "version id", then it's hard to go do
> compatibility of old readers reading new data.

My proposal was:

"3. Schemas match as per the current matching rules, even if the revisions
do not match."

That is, since Person_v2 and Person_v1 have the same name "Person" and
different revisions v2 and v1, they would match according to the current
rules.

Thiru