查看紀錄檔

1. 過一段時間，查看紀錄檔，得知從 context 表查詢訪客 (roleid=6) 權限，花費最多查詢時間。

   [root@moodle ~]# mysqldumpslow -s r -t 1 /var/lib/mysql/mysql.slow.log
   SELECT ctx.path,
                      rc.capability, rc.permission
                 FROM context ctx
                 JOIN role_capabilities rc ON rc.contextid = ctx.id
            LEFT JOIN context cctx
                      ON (cctx.contextlevel = 50 AND ctx.path LIKE CONCAT(cctx.path, '/%'))
                WHERE rc.roleid = '6' AND cctx.id IS NULL;