1、update 连接两个表
UPDATE ask_way a
SET way_addr = (
SELECT
q.ans_txt
FROM
pos_ques q
WHERE
a.hos_id = q.hos_id
AND a.way_nam = q.qus_txt
GROUP BY q.ans_txt
LIMIT 1
)
WHERE
hos_id = '30003000'
UPDATE ask_way a
SET way_addr = (
SELECT
q.ans_txt
FROM
pos_ques q
WHERE
a.hos_id = q.hos_id
AND a.way_nam = q.qus_txt
GROUP BY q.ans_txt
LIMIT 1
)
WHERE
hos_id = '30003000'