When I execute some queries ...
I got the error message /* SQL Error (2013): Lost connection to MySQL server during query */
and the my maria db restart / reboot the process..
but other queries fine...

<here is the query>

SELECT A.CONNECT_SYSTEM, B.USER_NO, B.USER_NAME, A.CONNECT_POSITION_NAME,
A.CONNECT_DEPT_CODE, A.CONNECT_DEPT_NAME, COUNT(DISTINCT(DATE_FORMAT(A.CONNECT_DATE, '%Y.%m.%d'))) AS DAY_CNT, COUNT AS CONNECT_CNT, ROW_NUMBER() OVER (PARTITION BY A.CONNECT_SYSTEM ORDER BY A.CONNECT_SYSTEM,COUNT DESC)
FROM rndp.TB_SPT_GCLOUD_CONNECT_LOG A
LEFT JOIN rndp.TB_SYS_USER B ON B.USER_NO = A.CONNECT_USER_NO AND A.CONNECT_USER_NO IS NOT NULL
WHERE 1=1 AND A.CONNECT_RESULT = '1' AND A.CONNECT_MSG = '[ ].'
GROUP BY A.CONNECT_SYSTEM, B.USER_NO, B.USER_NAME, A.CONNECT_POSITION_NAME,
A.CONNECT_DEPT_CODE, A.CONNECT_DEPT_NAME;