MySQL Snapshot Modes

When a MySQL connecor is started, there are various options. The default is when_needed. The other options may be useful from time to time.

InitialThe connector runs a snapshot if no offsets have been recorded for the logical server name
when_neededThe connector runs a snapshot upon startup when no offsets are available or when a previously recorded offset refers to a binlog location or GTID that is unavailable on the server
neverThe connector never uses snapshots. On first startup with a logical server name, the connector reads from the beginning of the binlog. Use this carefully when the entire database history is guaranteed to be in the binlog
schema_onlyThe connector runs a snapshot of schemas but not data. Useful when consistent data snapshots are not needed, only changes since the connector started
schema_only_recoveryA recovery setting for a connector already capturing changes. Enables recovery of a corrupted or lost database schema history topic. Can be periodically used to clean up unexpected growth in the database schema history topic, which requires infinite retention