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DATE_FORMAT(date,format)

Formats the date value according to the format string.

The following specifiers may be used in the format string. The % character is required before format specifier characters.

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#查询事务隔离级别
SELECT @@GLOBAL.tx_isolation,@@tx_isolation;

#设置事务隔离级别 read committed
SET SESSION TRANSACTION ISOLATION LEVEL READ COMMITTED;
SET GLOBAL TRANSACTION ISOLATION LEVEL READ COMMITTED;

Mysql服务启动

启动

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service mysqld start

停止

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service mysqld stop

重启

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service mysqld restart

问题:数据量达百万级别根据日期查询效率特别慢。create_time是datetime类型,转换为日期再匹配,需要查询出所有行进行过滤。

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