mongodb入门-4数据类型--日期、数组
mongodb入门-4数据类型--日期、数组 日期 在mongodb中创建日期的时候使用不同的方式创建的日期是不同的。 在mongodb中使用Date()创建的日期类型是一个字符串的类型,这个字符串中包含时区等数据 。使用new Date()创建的将会是ISODate类型的一个日期对象。同
mongodb入门-4数据类型--日期、数组
日期
在mongodb中创建日期的时候使用不同的方式创建的日期是不同的。
在mongodb中使用Date()创建的日期类型是一个字符串的类型,这个字符串中包含时区等数据 。使用new Date()创建的将会是ISODate类型的一个日期对象。同样我们可以使用ISODate()方式去创建日期对象,得到的结果是使用new Date相同的。下面是我在电脑上测试的:
在这里需要强调一点,在写程序的时候一定要使用正确的类型,防止我们以后做查找的时候类型匹配错误,比如我们开始创建文档的时候使用的Date(),它返回的是字符串,我们查找的时候却用对象去比较那就查找不到了。
数组
在mongodb中的数组是比较灵活的,数组中的元素可以是不同的。

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