CREATE TABLE clazz_audit_log (
    id VARCHAR PRIMARY KEY,
    clazz_id VARCHAR NOT NULL,
    action VARCHAR NOT NULL,
    operator_hty_id VARCHAR NOT NULL,
    operator_name VARCHAR,
    changes JSONB,
    created_at TIMESTAMP NOT NULL DEFAULT NOW(),
    org_id VARCHAR
);

CREATE INDEX idx_clazz_audit_log_clazz_id ON clazz_audit_log (clazz_id);
CREATE INDEX idx_clazz_audit_log_created_at ON clazz_audit_log (created_at);