ob执行sql报Lost connection to MySQL server during query

【 使用环境 】测试环境
【 OB or 其他组件 】ob
【 使用版本 】4.1.0-ce
【问题描述】在执行下面sql时,刚登陆数据库,执行前两次都报ERROR 2013 (HY000): Lost connection to MySQL server during query错误,后面再执行就不报错了,是怎么回事:


如果去掉变量部分,执行就没问题:

下面是timeout参数:

sql文本如下:

select count(0) from (SELECT
CH_NAME AS chName,
CH_CDE AS chCde,
FA_CH_NAME AS faChName,
FA_CH_CDE AS faChCde,
CH_LINK AS chLink,
CH_STATUS AS chStatus,
CH_DAY_LIMIT AS chDayLimit,
RMK AS RMK,
VERSION AS version,
@le:= IF (FA_CH_CDE = -1 ,0,IF( LOCATE( CONCAT(’|’,FA_CH_CDE,’:’),@pathlevel) > 0,SUBSTRING_INDEX( SUBSTRING_INDEX(@pathlevel,CONCAT(’|’,FA_CH_CDE,’:’),-1),’|’,1) +1,@le+1) ) levels,
@pathlevel:= CONCAT(@pathlevel,’|’,CH_CDE,’:’, @le ,’|’) pathlevel,
@pathnodes:= IF( FA_CH_CDE =-1,’,root’, CONCAT_WS(’,’,IF( LOCATE( CONCAT(’|’,FA_CH_CDE,’:’),@pathall) > 0 ,SUBSTRING_INDEX( SUBSTRING_INDEX(@pathall,CONCAT(’|’,FA_CH_CDE,’:’),-1),’|’,1),@pathnodes ) ,FA_CH_CDE ) )paths,
@pathall:=CONCAT(@pathall,’|’,CH_CDE,’:’, @pathnodes ,’|’) pathall
FROM CH_CHANNEL_INFO,
(
SELECT
@le:=0,
@pathlevel:=’’,
@pathall:=’’,
@pathnodes:=’’
) vv
where 1=1
AND FA_CH_CDE != ‘-1’
ORDER BY FA_CH_CDE,CH_CDE) tmp_count;

【复现路径】问题出现前后相关操作
【问题现象及影响】

【附件】

ch_channel_info建表结构需要提供下。
简单测试了下,执行正常的。
Create table CH_CHANNEL_INFO (CH_CDE varchar(10));

select count(0) from
(SELECT
CH_CDE AS chCde,
@pathlevel:= CONCAT(@pathlevel,’|’,CH_CDE,’:’) pathlevel
FROM CH_CHANNEL_INFO,
(SELECT
@pathlevel:=’’) vv
where 1=1
ORDER BY CH_CDE) tmp_count;