为大家分享一个之前遇到的sql执行问题，报错语法问题：
环境 ob v4.2 租户： ob mysql
sql 查询报错：
select t.rule_code,t.rule_name,t.rule_detail from t_ant_person_case_rule t
where
t.regist_no = ‘070201030120’
and t.valid_ind = ‘1’
and t.rule_ind = ‘3’
order by rule_code asc
UNION
select t.rule_code,t.rule_name,t.rule_detail from t_ant_vehicle_case_rule t
where
t.regist_no = ‘070201030120’
and t.valid_ind = ‘1’
and t.rule_ind = ‘3’
order by rule_code asc
UNION
select t.rule_code,t.rule_name,t.rule_detail from t_ant_repairfactory_case_rule t
where
t.regist_no = ‘070201030120’
and t.valid_ind = ‘1’
and t.rule_ind = ‘3’
order by rule_code asc
经分析，和union 前的order by 有关，
v4 版本再支持这种写法，在sql 最后一行保留一个order不用即可，供大家学习