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https://issues.apache.org/jira/browse/AVRO-160?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12790879#action_12790879
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Scott Carey commented on AVRO-160:
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{quote}Who's silently skipping blocks?{quote}
Code that jumps to the middle of the file and finds the start of the next block
by finding the sync marker and either:
1: there is a collision and it skips to the next sync marker rather than
failing.
2: the file was written corruptly (a sync marker is missing or corrupted on
write; block size/count are wrong but consistent with each other), a reader or
file split that assumes correctness can skip data silently on a seek and scan.
Detecting and failing on these conditions is important, no matter how unlikely.
Making test files that contain these flaws is also easy.
> file format should be friendly to streaming
> -------------------------------------------
>
> Key: AVRO-160
> URL: https://issues.apache.org/jira/browse/AVRO-160
> Project: Avro
> Issue Type: Improvement
> Components: spec
> Reporter: Doug Cutting
> Assignee: Doug Cutting
>
> It should be possible to stream through an Avro data file without seeking to
> the end.
> Currently the interpretation is that schemas written to the file apply to all
> entries before them. If this were changed so that they instead apply to all
> entries that follow, and the initial schema is written at the start of the
> file, then streaming could be supported.
> Note that the only change permitted to a schema as a file is written is to,
> if it is a union, to add new branches at the end of that union. If it is not
> a union, no changes may be made. So it is still the case that the final
> schema in a file can read every entry in the file and thus may be used to
> randomly access the file.
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