Oracle数据库日期过滤方法性能比较
Oracle数据库日期过滤方法性能比较。在开发SQL时，过滤日期段是经常遇到的情况，如何高效的过滤出日期段？本文通过实验进行验证：
Oracle数据库日期过滤方法性能比较
在开发SQL时，过滤日期段是经常遇到的情况，，如何高效的过滤出日期段？本文通过实验进行验证：
方法一、通过to_char将日期转换成字符串进行比较
to_char(cr.contractenddate, 'YYYY-MM-DD') >= '2014-11-13'
and to_char(cr.contractenddate, 'YYYY-MM-DD')
耗时：0.171s
方法二、通过to_date将字符串转换成日期进行比较
cr.contractenddate >= to_date('2014-11-13', 'YYYY-MM-DD')
and cr.contractenddate
耗时：0.093s
方法三、通过数据库关键字between and 进行比较
cr.contractenddate
between to_date('2014-11-13', 'YYYY-MM-DD') and to_date('2015-11-19', 'YYYY-MM-DD')
耗时：0.078s
总结：方法一耗时体现在需要逐个比较字符串的每个字符；
方法二耗时体现在>= 和
推荐使用方法三
本文永久更新链接地址：
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