[SUPPORT]In the scenario of writing from mysql cdc to hudi use flink，does hudi already supported schema evolution？

[Tomccat3]

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I'm using flink ingest data from mysql to hudi，but I'm running into a problem： mysql table schema will change，i want implement automatic schema evolution， does hudi already support this requirement, or is it already in development

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[Tomccat3]

@danny0405 Hello Danny, can you help me with this problem?

[ad1happy2go]

@Tomccat3 Hudi should support it. Are you facing issues? What kind of schema changes you are having?

[danny0405]

@Tomccat3 , schema evolution in Hudi is supported, but not automatically, you still need to alter the table schema manually and maybe restart the writing job.

[voonhous]

Commenting for visibility as this might be a feature-request for implicit comprehensive schema evolution for Hudi-on-Flink.

[Tomccat3]

@Tomccat3 , schema evolution in Hudi is supported, but not automatically, you still need to alter the table schema manually and maybe restart the writing job.

Thanks for your reply, i don't want to restart the writing job, can schema evolution be made automatic in flink datastream job?

[Tomccat3]

@Tomccat3 Hudi should support it. Are you facing issues? What kind of schema changes you are having?

For example:

1. I have a flink datastream job consume mysql binlog and then write to hudi 。
2. When the upstream mysql table schema has changed，i need to alter hudi table schema manually, and restart the flink job, i hope it can be made automatic。

[danny0405]

be made automatic in flink datastream job

No, the open source Flink does no support pass the schema around to the sink, that is a tricky part for Hudi to track the schema changes dynamically.

[Tomccat3]

No, the open source Flink does no support pass the schema around to the sink,

ok, what if we implement a RowData with schema?

[danny0405]

yeah, possible, you can pass around the schema together with the RowData, before each commit, you can overwrite the schema with the latest schema, only feasible for Flink DataStream API.