[{"payAmount":"375000","payChannelCode":"BOC"},{"payAmount":"376000","payChannelCode":"ABC"}]

 select pay_order_id,tag1,bill_date
from (
select pay_order_id,substr(acquire_type,2,length(acquire_type)-2) tags,bill_date from dd.PAYCHANNELDETAIL
) ta  lateral view explode(split(tags, '},')) r1 as tag1
;

1603150000007617360	{"payAmount":"375000","payChannelCode":"BOC"}	2016-03-15
1603150000007617360	{"payAmount":"376000","payChannelCode":"ABC"}	2016-03-15

SELECT 
pay_order_id,
get_json_object(subjson,'$.payAmount') as payAmount,
get_json_object(subjson,'$.payChannelCode') as payChannelCode,
bill_date
FROM
dd.PAYCHANNELDETAIL_SUBJSON