To extract the date portion from a DATETIME value, you use the DATE function as follows: SELECT Code language: SQL (Structured Query Language) ( sql ) To query the value of the variable, you use the following SELECT statement: SELECT Code language: SQL (Structured Query Language) ( sql ) MySQL DATE function SET = NOW() Code language: SQL (Structured Query Language) ( sql ) The following statement sets the variable to the current date and time using the NOW() function. It means that if you use the TIMESTAMP data to store date and time values, you should take a serious consideration when you move your database to a server located in a different time zone. This is because the TIMESTAMP column stores the date and time value in UTC when we changed the time zone, the value of the TIMESTAMP column is adjusted according to the new time zone. SET time_zone = '+03:00' Īs you can see, the value in the TIMESTAMP column is different. Timestamp_n_datetime Code language: SQL (Structured Query Language) ( sql )īoth values in DATETIME and TIMESTAMP columns are the same.įinally, set the connection’s time zone to +03:00 and query data from the timestamp_n_datetime table again. VALUES( NOW(), NOW()) Code language: SQL (Structured Query Language) ( sql )Īfter that, query data from the timestamp_n_datetime table. Then, insert the current date and time into both ts and dt columns of the timestamp_n_datetime table, INSERT INTO timestamp_n_datetime(ts,dt) ) Code language: SQL (Structured Query Language) ( sql ) Next, create a table named timestamp_n_datetime that consists of two columns: ts and dt with TIMESTAMP and DATETIME types using the following statement. SET time_zone = '+00:00' Code language: SQL (Structured Query Language) ( sql ) Let’s see the following example.įirst, set the timezone of the current connection to +00:00. MySQL stores TIMESTAMP in UTC value. However, MySQL stores the DATETIME value as is without timezone. If you want to store temporal values that are beyond 2038, you should use DATETIME instead of TIMESTAMP. TIMESTAMP values range from 00:00:01 UTC to 03:14:07 UTC. Both TIMESTAMP and DATETIME require additional bytes for fractional seconds precision. The TIMESTAMP requires 4 bytes while DATETIME requires 5 bytes. MySQL provides another temporal data type that is similar to the DATETIME called TIMESTAMP. Note that before MySQL 5.6.4, DATETIME values requires 8 bytes storage instead of 5 bytes. 999999 while 10:01:00.9 requires only 6 bytes, 1 byte for the fractional second precision. When including the fractional second precision, DATETIME values require more storage as illustrated in the following table: Fractional Seconds Precisionįor example, 10:01:00.999999 requires 8 bytes, 5 bytes for 10:01:00 and 3 bytes for. In addition, a DATETIME value can include a trailing fractional second up to microseconds with the format YYYY-MM-DD HH:MM:SS e.g., 10:01:00.999999. When you query data from a DATETIME column, MySQL displays the DATETIME value in the following format: YYYY-MM-DD HH:MM:SS Code language: SQL (Structured Query Language) ( sql )īy default, DATETIME values range from 00:00:00 to 23:59:59.Ī DATETIME value uses 5 bytes for storage. You use MySQL DATETIME to store a value that contains both date and time. Summary: in this tutorial, you will learn about MySQL DATETIME data type and how to use some handy functions for manipulating DATETIME effectively.
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