How to set time in MySQL
MySQL is an open source relational database management system. In MySQL, time is a very important data type. This article will discuss how to set the time in MySQL.
First of all, MySQL supports multiple time formats, including DATE, TIME, DATETIME and TIMESTAMP. Each of these four formats has its specific purpose.
DATE format represents the date, the format is "YYYY-MM-DD", where "YYYY" represents the year, "MM" represents the month, and "DD" represents the date.
TIME format represents time, the format is "HH:MM:SS", where "HH" represents hours, "MM" represents minutes, and "SS" represents seconds.
DATETIME format represents date and time, the format is "YYYY-MM-DD HH:MM:SS".
TIMESTAMP format is similar to DATETIME, but its value is based on a Unix timestamp and represents the number of seconds that have elapsed since January 1, 1970 00:00:00 UTC (Coordinated Universal Time).
To set the time, you can use MySQL's built-in function NOW(). This function returns the DATETIME value of the current date and time.
For example, to insert a DATETIME value into a time column in a table, use the following syntax:
INSERT INTO table_name (time_column) VALUES (NOW());
This statement inserts a DATETIME value for the current date and time into the time_column column.
For the TIMESTAMP column, you can use the TODAY() function to set the time. This function returns the UNIX timestamp of the current date.
For example, to insert the UNIX timestamp of the current time into the timestamp_column column in the table, use the following syntax:
INSERT INTO table_name (timestamp_column) VALUES (UNIX_TIMESTAMP());
This statement inserts the UNIX timestamp of the current date and time into the timestamp_column column .
In MySQL, you can also use the DATE_ADD() and DATE_SUB() functions to increase or decrease time.
For example, to add 7 days to the current date, use the following syntax:
SELECT DATE_ADD(NOW(), INTERVAL 7 DAY);
This statement will return the DATETIME value for the date and time seven days from now.
To set the correct time in MySQL, you also need to understand the time zone setting of the MySQL server. You can use the following statement to view the current time zone setting of the server:
SELECT @@global.time_zone;
If the time zone setting is incorrect, you can use the following statement to change the time zone setting:
SET @@global.time_zone = 'Asia/Shanghai';
This statement sets the time zone to China Standard Time , can also be changed according to the actual situation.
In short, setting time in MySQL requires understanding different time formats and MySQL built-in functions, and paying attention to the server's time zone setting. Using the correct methods and settings, you can ensure time accuracy and consistency.
The above is the detailed content of How to set time in MySQL. For more information, please follow other related articles on the PHP Chinese website!

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