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Home Database Mysql Tutorial MySQL中DATETIME跟TIMESTAMP的區(qū)別

MySQL中DATETIME跟TIMESTAMP的區(qū)別

Jun 07, 2016 pm 04:26 PM
datetime mysql timestamp the difference

MySQL中DATETIME和TIMESTAMP的區(qū)別 先Copy一份文檔給大家看: DateTime A date and time combination. The supported range is '1000-01-01 00:00:00' to '9999-12-31 23:59:59'. MySQL displays DATETIME values in 'YYYY-MM-DD HH:MM:SS' format, but allow

MySQL中DATETIME和TIMESTAMP的區(qū)別

先Copy一份文檔給大家看:

DateTime
A date and time combination. The supported range is '1000-01-01 00:00:00' to '9999-12-31 23:59:59'.
?MySQL displays DATETIME values in 'YYYY-MM-DD HH:MM:SS' format, but allows you to assign values to DATETIME columns using either strings or numbers.
TimeStamp
A timestamp. The range is '1970-01-01 00:00:00' to partway through the year 2037.?
A TIMESTAMP column is useful for recording the date and time of an INSERT or UPDATE operation.?
The first TIMESTAMP column in a table is automatically set to the date and time of the most recent operation if you don't assign it a value yourself.?
You can also set any TIMESTAMP column to the current date and time by assigning it a NULL value.

現(xiàn)在開始具體比較:

DATETIME,字節(jié)數(shù)為8,取值范圍為“1000-01-01 00:00:00——9999-12-31 23:59:59”

? ? ? ? ? ? ? ?對應(yīng)Java類型為java.sql.Timestamp

? ? ? ? ? ?INSERT或UPDATE操作時系統(tǒng)不會自動修改其值,不可以設(shè)定默認(rèn)值,為必須字段時必須手動插入,建議使用:new()

? ? ? ? ? ? ? ?MySql按照YYYY-MM-DD HH:MM:SS對數(shù)據(jù)進(jìn)行格式化,允許以字符串和數(shù)字的方式提交

? ? ? ? ? ? ? ? ? eg:insert into time_table(CreateDate) values(‘2014-06-09 15:01:01’)

? ? ? ? ? ? ? ? ? ?或insert into time_table(CreateDate) values(‘20140609150101’)

TIMESTAMP,字節(jié)數(shù)為4,取值范圍為“19700101080001——20380119111407”

? ? ? ? ? ? ? ?對應(yīng)Java類型為java.sql.Timestamp

? ? ? ? ? ? ? ?INSERT或UPDATE操作時(且未手動賦值)系統(tǒng)會自動更新、插入當(dāng)前系統(tǒng)時間,默認(rèn)值為CURRENT_TIMESTAMP()

? ? ? ? ? ? ? ? ? ? ? ? ? ? ?提交手動賦值為NULL時也會被賦值為當(dāng)前系統(tǒng)時間,錯誤時會填入0

? ? ? ? ? ? ? ?使用TIMESTAMP一定要注意他的時間范圍(見上)。

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