使用GROUP BY进行分组,同时取出最新的一条

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SELECT client_id,group_concat(credit_id ORDER BY credit_id DESC) FROM client_credit GROUP BY client_id
client_id    group_concat(credit_id ORDER BY credit_id DESC)
56    22,20
65    5,4,3,1
107    7
108    6
113    19,18,17,16,15,14,13,12,11,10,9,8