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  • MySql5.6中的表按照时间进行表分区过程中遇到的坑

    前言:最近的记忆力越来越差了,好多项目中刚刚做过的技术,过段时间就忘记了。所以不得不开始写博客了,把平时遇到的一些bug排除过程和尝试的新技术记录下来。

    项目中有一张表有上亿的数据,根据业务的需求,需要对该表按照时间(每个月)进行表分区。PS:该项目的数据库之前一直是sql server,现在由于客户的要求,改为Mysql。

    先说一下总结,再慢慢讲一下填坑的过程:

    对于mysql5.6.27版本里有两种时间格式的数据类型:datetime和timestamp。RANGE分区,如果是datetime:应使用TO_DAYS()这个函数。我的具体代码如下:

    ALTER TABLE t_ec_energyitemhourresult 
    PARTITION BY RANGE(TO_DAYS(F_StartHour))
    (
    PARTITION p0 VALUES LESS THAN (TO_DAYS('2012-01-01')), 
    PARTITION p1 VALUES LESS THAN (TO_DAYS('2012-02-01')), 
    PARTITION p2 VALUES LESS THAN (TO_DAYS('2012-03-01')), 
    PARTITION p3 VALUES LESS THAN (TO_DAYS('2012-04-01')), 
    PARTITION p4 VALUES LESS THAN (TO_DAYS('2012-05-01')), 
    PARTITION p5 VALUES LESS THAN (TO_DAYS('2012-06-01')), 
    PARTITION p6 VALUES LESS THAN (TO_DAYS('2012-07-01')), 
    PARTITION p7 VALUES LESS THAN (TO_DAYS('2012-08-01')), 
    PARTITION p8 VALUES LESS THAN (TO_DAYS('2012-09-01')), 
    PARTITION p9 VALUES LESS THAN (TO_DAYS('2012-10-01')), 
    PARTITION p10 VALUES LESS THAN (TO_DAYS('2012-11-01')), 
    PARTITION p11 VALUES LESS THAN (TO_DAYS('2012-12-01')), 
    PARTITION p12 VALUES LESS THAN (TO_DAYS('2013-01-01')), 
    PARTITION p13 VALUES LESS THAN (TO_DAYS('2013-02-01')), 
    PARTITION p14 VALUES LESS THAN (TO_DAYS('2013-03-01')), 
    PARTITION p15 VALUES LESS THAN (TO_DAYS('2013-04-01')), 
    PARTITION p16 VALUES LESS THAN (TO_DAYS('2013-05-01')), 
    PARTITION p17 VALUES LESS THAN (TO_DAYS('2013-06-01')), 
    PARTITION p18 VALUES LESS THAN (TO_DAYS('2013-07-01')), 
    PARTITION p19 VALUES LESS THAN (TO_DAYS('2013-08-01')), 
    PARTITION p20 VALUES LESS THAN (TO_DAYS('2013-09-01')), 
    PARTITION p21 VALUES LESS THAN (TO_DAYS('2013-10-01')), 
    PARTITION p22 VALUES LESS THAN (TO_DAYS('2013-11-01')), 
    PARTITION p23 VALUES LESS THAN (TO_DAYS('2013-12-01')), 
    PARTITION p24 VALUES LESS THAN (TO_DAYS('2014-01-01')), 
    PARTITION p25 VALUES LESS THAN (TO_DAYS('2014-02-01')), 
    PARTITION p26 VALUES LESS THAN (TO_DAYS('2014-03-01')), 
    PARTITION p27 VALUES LESS THAN (TO_DAYS('2014-04-01')), 
    PARTITION p28 VALUES LESS THAN (TO_DAYS('2014-05-01')), 
    PARTITION p29 VALUES LESS THAN (TO_DAYS('2014-06-01')), 
    PARTITION p30 VALUES LESS THAN (TO_DAYS('2014-07-01')), 
    PARTITION p31 VALUES LESS THAN (TO_DAYS('2014-08-01')), 
    PARTITION p32 VALUES LESS THAN (TO_DAYS('2014-09-01')), 
    PARTITION p33 VALUES LESS THAN (TO_DAYS('2014-10-01')), 
    PARTITION p34 VALUES LESS THAN (TO_DAYS('2014-11-01')), 
    PARTITION p35 VALUES LESS THAN (TO_DAYS('2014-12-01')), 
    PARTITION p36 VALUES LESS THAN (TO_DAYS('2015-01-01')), 
    PARTITION p37 VALUES LESS THAN (TO_DAYS('2015-02-01')), 
    PARTITION p38 VALUES LESS THAN (TO_DAYS('2015-03-01')), 
    PARTITION p39 VALUES LESS THAN (TO_DAYS('2015-04-01')), 
    PARTITION p40 VALUES LESS THAN (TO_DAYS('2015-05-01')), 
    PARTITION p41 VALUES LESS THAN (TO_DAYS('2015-06-01')), 
    PARTITION p42 VALUES LESS THAN (TO_DAYS('2015-07-01')), 
    PARTITION p43 VALUES LESS THAN (TO_DAYS('2015-08-01')), 
    PARTITION p44 VALUES LESS THAN (TO_DAYS('2015-09-01')), 
    PARTITION p45 VALUES LESS THAN (TO_DAYS('2015-10-01')), 
    PARTITION p46 VALUES LESS THAN (TO_DAYS('2015-11-01')), 
    PARTITION p47 VALUES LESS THAN (TO_DAYS('2015-12-01')), 
    PARTITION p48 VALUES LESS THAN (TO_DAYS('2016-01-01')), 
    PARTITION p49 VALUES LESS THAN (TO_DAYS('2016-02-01')), 
    PARTITION p50 VALUES LESS THAN (TO_DAYS('2016-03-01')), 
    PARTITION p51 VALUES LESS THAN (TO_DAYS('2016-04-01')), 
    PARTITION p52 VALUES LESS THAN (TO_DAYS('2016-05-01')), 
    PARTITION p53 VALUES LESS THAN (TO_DAYS('2016-06-01')), 
    PARTITION p54 VALUES LESS THAN (TO_DAYS('2016-07-01')), 
    PARTITION p55 VALUES LESS THAN (TO_DAYS('2016-08-01')), 
    PARTITION p56 VALUES LESS THAN (TO_DAYS('2016-09-01')), 
    PARTITION p57 VALUES LESS THAN (TO_DAYS('2016-10-01')), 
    PARTITION p58 VALUES LESS THAN (TO_DAYS('2016-11-01')), 
    PARTITION p59 VALUES LESS THAN (TO_DAYS('2016-12-01')), 
    PARTITION p60 VALUES LESS THAN (TO_DAYS('2017-01-01')), 
    PARTITION p61 VALUES LESS THAN (TO_DAYS('2017-02-01')), 
    PARTITION p62 VALUES LESS THAN (TO_DAYS('2017-03-01')), 
    PARTITION p63 VALUES LESS THAN (TO_DAYS('2017-04-01')), 
    PARTITION p64 VALUES LESS THAN (TO_DAYS('2017-05-01')), 
    PARTITION p65 VALUES LESS THAN (TO_DAYS('2017-06-01')), 
    PARTITION p66 VALUES LESS THAN (TO_DAYS('2017-07-01')), 
    PARTITION p67 VALUES LESS THAN (TO_DAYS('2017-08-01')), 
    PARTITION p68 VALUES LESS THAN (TO_DAYS('2017-09-01')), 
    PARTITION p69 VALUES LESS THAN (TO_DAYS('2017-10-01')), 
    PARTITION p70 VALUES LESS THAN (TO_DAYS('2017-11-01')), 
    PARTITION p71 VALUES LESS THAN (TO_DAYS('2017-12-01')), 
    PARTITION p72 VALUES LESS THAN (TO_DAYS('2018-01-01')), 
    PARTITION p73 VALUES LESS THAN (TO_DAYS('2018-02-01')), 
    PARTITION p74 VALUES LESS THAN (TO_DAYS('2018-03-01')), 
    PARTITION p75 VALUES LESS THAN (TO_DAYS('2018-04-01')), 
    PARTITION p76 VALUES LESS THAN (TO_DAYS('2018-05-01')), 
    PARTITION p77 VALUES LESS THAN (TO_DAYS('2018-06-01')), 
    PARTITION p78 VALUES LESS THAN (TO_DAYS('2018-07-01')), 
    PARTITION p79 VALUES LESS THAN (TO_DAYS('2018-08-01')), 
    PARTITION p80 VALUES LESS THAN (TO_DAYS('2018-09-01')), 
    PARTITION p81 VALUES LESS THAN (TO_DAYS('2018-10-01')), 
    PARTITION p82 VALUES LESS THAN (TO_DAYS('2018-11-01')), 
    PARTITION p83 VALUES LESS THAN (TO_DAYS('2018-12-01')), 
    PARTITION p84 VALUES LESS THAN (TO_DAYS('2019-01-01')), 
    PARTITION p85 VALUES LESS THAN (TO_DAYS('2019-02-01')), 
    PARTITION p86 VALUES LESS THAN (TO_DAYS('2019-03-01')), 
    PARTITION p87 VALUES LESS THAN (TO_DAYS('2019-04-01')), 
    PARTITION p88 VALUES LESS THAN (TO_DAYS('2019-05-01')), 
    PARTITION p89 VALUES LESS THAN (TO_DAYS('2019-06-01')), 
    PARTITION p90 VALUES LESS THAN (TO_DAYS('2019-07-01')), 
    PARTITION p91 VALUES LESS THAN (TO_DAYS('2019-08-01')), 
    PARTITION p92 VALUES LESS THAN (TO_DAYS('2019-09-01')), 
    PARTITION p93 VALUES LESS THAN (TO_DAYS('2019-10-01')), 
    PARTITION p94 VALUES LESS THAN (TO_DAYS('2019-11-01')), 
    PARTITION p95 VALUES LESS THAN (TO_DAYS('2019-12-01')), 
    PARTITION p96 VALUES LESS THAN (TO_DAYS('2020-01-01')), 
    PARTITION p97 VALUES LESS THAN (TO_DAYS('2020-02-01')), 
    PARTITION p98 VALUES LESS THAN (TO_DAYS('2020-03-01')), 
    PARTITION p99 VALUES LESS THAN (TO_DAYS('2020-04-01')), 
    PARTITION p100 VALUES LESS THAN (TO_DAYS('2020-05-01')), 
    PARTITION p101 VALUES LESS THAN (TO_DAYS('2020-06-01')), 
    PARTITION p102 VALUES LESS THAN (TO_DAYS('2020-07-01')), 
    PARTITION p103 VALUES LESS THAN (TO_DAYS('2020-08-01')), 
    PARTITION p104 VALUES LESS THAN (TO_DAYS('2020-09-01')), 
    PARTITION p105 VALUES LESS THAN (TO_DAYS('2020-10-01')), 
    PARTITION p106 VALUES LESS THAN (TO_DAYS('2020-11-01')), 
    PARTITION p107 VALUES LESS THAN (TO_DAYS('2020-12-01')), 
    PARTITION p108 VALUES LESS THAN (TO_DAYS('2021-01-01')), 
    PARTITION p109 VALUES LESS THAN (MAXVALUE)
    );

    如果是timestamp类型,应使用UNIX_TIMESTAMP函数转换一下。

    ALTER TABLE t_ec_energyitemresult 
    PARTITION BY RANGE( UNIX_TIMESTAMP(F_StartTime))
    (
    PARTITION p0 VALUES LESS THAN (UNIX_TIMESTAMP('2012-01-01')), 
    PARTITION p1 VALUES LESS THAN (UNIX_TIMESTAMP('2012-02-01')), 
    PARTITION p2 VALUES LESS THAN (UNIX_TIMESTAMP('2012-03-01')), 
    PARTITION p3 VALUES LESS THAN (UNIX_TIMESTAMP('2012-04-01')), 
    PARTITION p4 VALUES LESS THAN (UNIX_TIMESTAMP('2012-05-01')), 
    PARTITION p5 VALUES LESS THAN (UNIX_TIMESTAMP('2012-06-01')), 
    PARTITION p6 VALUES LESS THAN (UNIX_TIMESTAMP('2012-07-01')), 
    PARTITION p7 VALUES LESS THAN (UNIX_TIMESTAMP('2012-08-01')), 
    PARTITION p8 VALUES LESS THAN (UNIX_TIMESTAMP('2012-09-01')), 
    PARTITION p9 VALUES LESS THAN (UNIX_TIMESTAMP('2012-10-01')), 
    PARTITION p10 VALUES LESS THAN (UNIX_TIMESTAMP('2012-11-01')), 
    PARTITION p11 VALUES LESS THAN (UNIX_TIMESTAMP('2012-12-01')), 
    PARTITION p12 VALUES LESS THAN (UNIX_TIMESTAMP('2013-01-01')), 
    PARTITION p13 VALUES LESS THAN (UNIX_TIMESTAMP('2013-02-01')), 
    PARTITION p14 VALUES LESS THAN (UNIX_TIMESTAMP('2013-03-01')), 
    PARTITION p15 VALUES LESS THAN (UNIX_TIMESTAMP('2013-04-01')), 
    PARTITION p16 VALUES LESS THAN (UNIX_TIMESTAMP('2013-05-01')), 
    PARTITION p17 VALUES LESS THAN (UNIX_TIMESTAMP('2013-06-01')), 
    PARTITION p18 VALUES LESS THAN (UNIX_TIMESTAMP('2013-07-01')), 
    PARTITION p19 VALUES LESS THAN (UNIX_TIMESTAMP('2013-08-01')), 
    PARTITION p20 VALUES LESS THAN (UNIX_TIMESTAMP('2013-09-01')), 
    PARTITION p21 VALUES LESS THAN (UNIX_TIMESTAMP('2013-10-01')), 
    PARTITION p22 VALUES LESS THAN (UNIX_TIMESTAMP('2013-11-01')), 
    PARTITION p23 VALUES LESS THAN (UNIX_TIMESTAMP('2013-12-01')), 
    PARTITION p24 VALUES LESS THAN (UNIX_TIMESTAMP('2014-01-01')), 
    PARTITION p25 VALUES LESS THAN (UNIX_TIMESTAMP('2014-02-01')), 
    PARTITION p26 VALUES LESS THAN (UNIX_TIMESTAMP('2014-03-01')), 
    PARTITION p27 VALUES LESS THAN (UNIX_TIMESTAMP('2014-04-01')), 
    PARTITION p28 VALUES LESS THAN (UNIX_TIMESTAMP('2014-05-01')), 
    PARTITION p29 VALUES LESS THAN (UNIX_TIMESTAMP('2014-06-01')), 
    PARTITION p30 VALUES LESS THAN (UNIX_TIMESTAMP('2014-07-01')), 
    PARTITION p31 VALUES LESS THAN (UNIX_TIMESTAMP('2014-08-01')), 
    PARTITION p32 VALUES LESS THAN (UNIX_TIMESTAMP('2014-09-01')), 
    PARTITION p33 VALUES LESS THAN (UNIX_TIMESTAMP('2014-10-01')), 
    PARTITION p34 VALUES LESS THAN (UNIX_TIMESTAMP('2014-11-01')), 
    PARTITION p35 VALUES LESS THAN (UNIX_TIMESTAMP('2014-12-01')), 
    PARTITION p36 VALUES LESS THAN (UNIX_TIMESTAMP('2015-01-01')), 
    PARTITION p37 VALUES LESS THAN (UNIX_TIMESTAMP('2015-02-01')), 
    PARTITION p38 VALUES LESS THAN (UNIX_TIMESTAMP('2015-03-01')), 
    PARTITION p39 VALUES LESS THAN (UNIX_TIMESTAMP('2015-04-01')), 
    PARTITION p40 VALUES LESS THAN (UNIX_TIMESTAMP('2015-05-01')), 
    PARTITION p41 VALUES LESS THAN (UNIX_TIMESTAMP('2015-06-01')), 
    PARTITION p42 VALUES LESS THAN (UNIX_TIMESTAMP('2015-07-01')), 
    PARTITION p43 VALUES LESS THAN (UNIX_TIMESTAMP('2015-08-01')), 
    PARTITION p44 VALUES LESS THAN (UNIX_TIMESTAMP('2015-09-01')), 
    PARTITION p45 VALUES LESS THAN (UNIX_TIMESTAMP('2015-10-01')), 
    PARTITION p46 VALUES LESS THAN (UNIX_TIMESTAMP('2015-11-01')), 
    PARTITION p47 VALUES LESS THAN (UNIX_TIMESTAMP('2015-12-01')), 
    PARTITION p48 VALUES LESS THAN (UNIX_TIMESTAMP('2016-01-01')), 
    PARTITION p49 VALUES LESS THAN (UNIX_TIMESTAMP('2016-02-01')), 
    PARTITION p50 VALUES LESS THAN (UNIX_TIMESTAMP('2016-03-01')), 
    PARTITION p51 VALUES LESS THAN (UNIX_TIMESTAMP('2016-04-01')), 
    PARTITION p52 VALUES LESS THAN (UNIX_TIMESTAMP('2016-05-01')), 
    PARTITION p53 VALUES LESS THAN (UNIX_TIMESTAMP('2016-06-01')), 
    PARTITION p54 VALUES LESS THAN (UNIX_TIMESTAMP('2016-07-01')), 
    PARTITION p55 VALUES LESS THAN (UNIX_TIMESTAMP('2016-08-01')), 
    PARTITION p56 VALUES LESS THAN (UNIX_TIMESTAMP('2016-09-01')), 
    PARTITION p57 VALUES LESS THAN (UNIX_TIMESTAMP('2016-10-01')), 
    PARTITION p58 VALUES LESS THAN (UNIX_TIMESTAMP('2016-11-01')), 
    PARTITION p59 VALUES LESS THAN (UNIX_TIMESTAMP('2016-12-01')), 
    PARTITION p60 VALUES LESS THAN (UNIX_TIMESTAMP('2017-01-01')), 
    PARTITION p61 VALUES LESS THAN (UNIX_TIMESTAMP('2017-02-01')), 
    PARTITION p62 VALUES LESS THAN (UNIX_TIMESTAMP('2017-03-01')), 
    PARTITION p63 VALUES LESS THAN (UNIX_TIMESTAMP('2017-04-01')), 
    PARTITION p64 VALUES LESS THAN (UNIX_TIMESTAMP('2017-05-01')), 
    PARTITION p65 VALUES LESS THAN (UNIX_TIMESTAMP('2017-06-01')), 
    PARTITION p66 VALUES LESS THAN (UNIX_TIMESTAMP('2017-07-01')), 
    PARTITION p67 VALUES LESS THAN (UNIX_TIMESTAMP('2017-08-01')), 
    PARTITION p68 VALUES LESS THAN (UNIX_TIMESTAMP('2017-09-01')), 
    PARTITION p69 VALUES LESS THAN (UNIX_TIMESTAMP('2017-10-01')), 
    PARTITION p70 VALUES LESS THAN (UNIX_TIMESTAMP('2017-11-01')), 
    PARTITION p71 VALUES LESS THAN (UNIX_TIMESTAMP('2017-12-01')), 
    PARTITION p72 VALUES LESS THAN (UNIX_TIMESTAMP('2018-01-01')), 
    PARTITION p73 VALUES LESS THAN (UNIX_TIMESTAMP('2018-02-01')), 
    PARTITION p74 VALUES LESS THAN (UNIX_TIMESTAMP('2018-03-01')), 
    PARTITION p75 VALUES LESS THAN (UNIX_TIMESTAMP('2018-04-01')), 
    PARTITION p76 VALUES LESS THAN (UNIX_TIMESTAMP('2018-05-01')), 
    PARTITION p77 VALUES LESS THAN (UNIX_TIMESTAMP('2018-06-01')), 
    PARTITION p78 VALUES LESS THAN (UNIX_TIMESTAMP('2018-07-01')), 
    PARTITION p79 VALUES LESS THAN (UNIX_TIMESTAMP('2018-08-01')), 
    PARTITION p80 VALUES LESS THAN (UNIX_TIMESTAMP('2018-09-01')), 
    PARTITION p81 VALUES LESS THAN (UNIX_TIMESTAMP('2018-10-01')), 
    PARTITION p82 VALUES LESS THAN (UNIX_TIMESTAMP('2018-11-01')), 
    PARTITION p83 VALUES LESS THAN (UNIX_TIMESTAMP('2018-12-01')), 
    PARTITION p84 VALUES LESS THAN (UNIX_TIMESTAMP('2019-01-01')), 
    PARTITION p85 VALUES LESS THAN (UNIX_TIMESTAMP('2019-02-01')), 
    PARTITION p86 VALUES LESS THAN (UNIX_TIMESTAMP('2019-03-01')), 
    PARTITION p87 VALUES LESS THAN (UNIX_TIMESTAMP('2019-04-01')), 
    PARTITION p88 VALUES LESS THAN (UNIX_TIMESTAMP('2019-05-01')), 
    PARTITION p89 VALUES LESS THAN (UNIX_TIMESTAMP('2019-06-01')), 
    PARTITION p90 VALUES LESS THAN (UNIX_TIMESTAMP('2019-07-01')), 
    PARTITION p91 VALUES LESS THAN (UNIX_TIMESTAMP('2019-08-01')), 
    PARTITION p92 VALUES LESS THAN (UNIX_TIMESTAMP('2019-09-01')), 
    PARTITION p93 VALUES LESS THAN (UNIX_TIMESTAMP('2019-10-01')), 
    PARTITION p94 VALUES LESS THAN (UNIX_TIMESTAMP('2019-11-01')), 
    PARTITION p95 VALUES LESS THAN (UNIX_TIMESTAMP('2019-12-01')), 
    PARTITION p96 VALUES LESS THAN (UNIX_TIMESTAMP('2020-01-01')), 
    PARTITION p97 VALUES LESS THAN (UNIX_TIMESTAMP('2020-02-01')), 
    PARTITION p98 VALUES LESS THAN (UNIX_TIMESTAMP('2020-03-01')), 
    PARTITION p99 VALUES LESS THAN (UNIX_TIMESTAMP('2020-04-01')), 
    PARTITION p100 VALUES LESS THAN (UNIX_TIMESTAMP('2020-05-01')), 
    PARTITION p101 VALUES LESS THAN (UNIX_TIMESTAMP('2020-06-01')), 
    PARTITION p102 VALUES LESS THAN (UNIX_TIMESTAMP('2020-07-01')), 
    PARTITION p103 VALUES LESS THAN (UNIX_TIMESTAMP('2020-08-01')), 
    PARTITION p104 VALUES LESS THAN (UNIX_TIMESTAMP('2020-09-01')), 
    PARTITION p105 VALUES LESS THAN (UNIX_TIMESTAMP('2020-10-01')), 
    PARTITION p106 VALUES LESS THAN (UNIX_TIMESTAMP('2020-11-01')), 
    PARTITION p107 VALUES LESS THAN (UNIX_TIMESTAMP('2020-12-01')), 
    PARTITION p108 VALUES LESS THAN (UNIX_TIMESTAMP('2021-01-01')), 
    PARTITION p109 VALUES LESS THAN (MAXVALUE)
    );

    下面是从mysql官网上copy下来的:

    In MySQL 5.6, range optimization can be used for the TO_DAYS()TO_SECONDS(), and YEAR() functions. In addition, beginning with MySQL 5.6.3, UNIX_TIMESTAMP() is treated as monotonic in partitioning expressions. 

    个人理解的就是:Mysql中Range分区不支持时间类型,需分别转换到正整数。其中的函数就是上述英文中蓝色的几个函数。

    说说这个坑:

    由于同事的mysql里的数据是通过SQLlog这个软件从sqlserver里导过来的。原来sqlserver分区列的datetime类型被转换成了mysql中的timestamp(6),当他执行分区语句的时候,总是报错:

     The PARTITION function returns the wrong type,提示返回了错误类型。而我的mysql里的数据是通过navicat这个软件从sqlserver里导过来的。一切正常。

    后来经过排查:发现我的timestamp长度为0.

    mysql> select UNIX_TIMESTAMP(CURRENT_TIMESTAMP);
    +-----------------------------------+
    | UNIX_TIMESTAMP(CURRENT_TIMESTAMP) |
    +-----------------------------------+
    | 1445306197 |
    +-----------------------------------+
    1 row in set

    mysql> select UNIX_TIMESTAMP(CURRENT_TIMESTAMP(6));
    +--------------------------------------+
    | UNIX_TIMESTAMP(CURRENT_TIMESTAMP(6)) |
    +--------------------------------------+
    | 1445306210.812460 |
    +--------------------------------------+
    1 row in set

    mysql> select CURRENT_TIMESTAMP;
    +---------------------+
    | CURRENT_TIMESTAMP |
    +---------------------+
    | 2015-10-20 09:57:42 |
    +---------------------+
    1 row in set

    mysql> select CURRENT_TIMESTAMP(6);
    +----------------------------+
    | CURRENT_TIMESTAMP(6) |
    +----------------------------+
    | 2015-10-20 09:57:53.970072 |
    +----------------------------+
    1 row in set

    因为timestamp(6)存储了6位微秒级,所以无法转换成整数了。

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  • 原文地址:https://www.cnblogs.com/neughj/p/4895501.html
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