The server_audit_timestamp_format %f specifier always rendered zero
microseconds. The server downcast the precise time to seconds before
passing it to audit plugins, and the plugin then re-fetched the time
itself at write time.
Pass the server's high-resolution time through the audit API instead:
- extend mysql_event_general with general_time_microseconds (added in
MYSQL_AUDIT_INTERFACE_VERSION 0x0304), keeping general_time in
seconds for backward compatibility
- the server_audit plugin uses event->general_time_microseconds for
query log entries instead of re-fetching the time at write time
Connection and table events carry no timestamp in the audit API, so the
plugin keeps taking the time at event time for those entries.
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