用到presto两个函数
1. from_unixtime
2.format_datetime
select ‘1566748800000‘, substr(‘1566748800000‘,1,10) as a, from_unixtime(cast(substr(‘1566748800000‘,1,10) as int)) as b, -- 将13位毫秒级的unix timestamp截取到秒级别 format_datetime(from_unixtime(cast(substr(‘1566748800000‘,1,10) as int)),‘yyyy-MM-dd‘)
转换结果
参考资料 https://prestodb.github.io/docs/current/functions/datetime.html
原文：https://www.cnblogs.com/MrZhangL/p/11417960.html