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      • First Time Event Tracker
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      • Schema Enforcer
      • Taxonomy Standardizer
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  • 0001-events-sample-by

Migration guide - 0001_events_sample_by

Last updated: Aug 09, 2022

0001_events_sample_by is a no-op test async migration. Note that on PostHog version 1.32 we automatically continue to run other migrations after a successful completion.

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Migration guide - 0002_events_sample_by

0002_events_sample_by is an async migration added to change the SAMPLE BY and ORDER BY clauses of our events table in ClickHouse. There were 2 important reasons for doing this: Performance: The new schema leads to a performance (speed) improvement for various PostHog queries Upgrading ClickHouse: Changing the schema was necessary to unblock the upgrading of ClickHouse, which is something we aim to complete in PostHog version 1.33.0 and can also bring massive performance improvements. Note…

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  • Paul Hultgren
    Paul Hultgren

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