MOLT Fetch failback mode #18990
MOLT Fetch failback mode #18990
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@ryanluu12345 Friendly ping for review! |
| --mode import-only | ||
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| #### Fail back to source database |
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Nit: are we using "fail back" or "failback" as two or one word(s) respectively?
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"Fail back" is the verb and "failback" is the noun for the operation, e.g., "you fail back by performing a failback operation". Does that make sense? ("Failback operation" is also redundant as we can just say "perform failback".)
| #### Fail back to source database | ||
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| {{site.data.alerts.callout_info}} | ||
| `failback` mode supports MySQL 8.0 and later. |
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Super nit: "mode only supports MySQL 8.0". Although with pending work this may change. So keep an eye out for 5.7 support that we're working on. We'll keep you posted.
| `failback` mode supports MySQL 8.0 and later. | ||
| {{site.data.alerts.end}} | ||
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| If you encounter issues after moving data to CockroachDB, you can use `failback` to replicate changes on CockroachDB back to the initial source database. In case you need to roll back the migration, this ensures that data is consistent on the source. |
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@rohan-joshi this is not the only case where customers fail back right? Sometimes, folks want to write data back just as a backup or if they want to keep their original DB up to date just in case right? Not only during failures.
src/current/molt/molt-fetch.md
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| --table-filter 'employees, payments' | ||
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| `failback` mode creates a [CockroachDB changefeed]({% link {{ site.current_cloud_version }}/change-data-capture-overview.md %}) that passes change events from CockroachDB to a [webhook sink]({% link {{ site.current_cloud_version }}/changefeed-sinks.md %}#webhook-sink). However, if there is already a running CockroachDB changefeed with the same webhook sink URL (excluding query parameters) and [watched rows]({% link {{ site.current_cloud_version }}/changefeed-sinks.md %}), the existing changefeed is used for `failback`. |
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Also it's not "watched rows", it's "watched tables". We match on same tables + same URL
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I'm using our CDC term "watched rows" which seems to mean the same thing. The rows being watched are the ones in the specified table names. See: https://www.cockroachlabs.com/docs/stable/change-data-capture-overview
Do you think this is too confusing? I assumed it was a standard CDC term. cc @rohan-joshi
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@ryanluu12345 Updated. PTAL! |
DOC-10978
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