SQL Anywhere Studio Security Guide
Keeping Your Data Secure
Auditing database activity
You can add comments to the audit trail using the sa_audit_string system stored procedure. It takes a single argument, which is a string of up to 200 bytes. You must have DBA permissions to call this procedure.
For example:
call sa_audit_string( 'Started audit testing here.' )
This comment is stored in the transaction log as an audit statement.