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Critical severityconfiguration

Power BI Refresh Error:
1594

What does this error mean?

The MySQL replica could not read its relay log — the relay log may be corrupted or missing.

Common causes

  • 1Relay log file was corrupted due to a disk error or server crash during write
  • 2Relay log index file is out of sync with the actual relay log files on disk
  • 3MySQL replica server was uncleanly shut down, leaving relay logs in an inconsistent state

How to fix it

  1. 1Step 1: Stop the replica: `STOP SLAVE;`
  2. 2Step 2: Reset the relay log: `RESET SLAVE;` (this deletes all relay logs — the replica will re-fetch from the primary).
  3. 3Step 3: Re-point to the primary and restart: `CHANGE MASTER TO MASTER_HOST='primary_host', MASTER_LOG_FILE='...', MASTER_LOG_POS=...; START SLAVE;`
  4. 4Step 4: Enable relay log recovery: add `relay_log_recovery=ON` to my.cnf to automatically recover from relay log corruption on restart.

Frequently asked questions

What does relay_log_recovery=ON do in MySQL?

It tells MySQL to automatically discard and re-fetch relay log contents from the primary on replica startup, recovering from relay log corruption without manual intervention.

Does RESET SLAVE lose any replication data?

RESET SLAVE deletes all relay log files and resets the replication position tracking. The replica will re-fetch events from the primary starting at the last committed position. No primary data is lost.

Can MetricSign detect when relay log failure causes pipeline failures?

Yes — MetricSign captures ADF pipeline failures and surfaces the MySQL error code in the incident detail, alerting you when replication issues start impacting data pipelines.

Official documentation: https://dev.mysql.com/doc/mysql-errors/8.0/en/server-error-reference.html

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