GROUP_CONCAT 可以将分组的字段进行拼接处理.
SELECT
g.id,
g.merchant_id,
g. NAME,
g.introduction,
g.cover_pic,
g.play_pic,
g.amount,
g.price,
g.audit_status,
g.audit_apply_time,
g.audit_update_time,
c.payment_ratio,
c.period,
m.id id1,
m.merchant_name
FROM
tb_goods_info g
LEFT JOIN (
SELECT
goods_id,
payment_ratio,
GROUP_CONCAT(period SEPARATOR '期,') AS period
FROM
tb_goods_config
GROUP BY
goods_id
) c ON g.id = c.goods_id
LEFT JOIN tb_merchant m ON g.merchant_id = m.id