CREATE TABLE tmp(Ĭreated_on DATETIME NOT NULL DEFAULT NOW() - or CURRENT_TIMESTAMP The created_on column has a default value specified by the NOW() function. Let’s take a look at the following example.įirst, create a new table named tmp with three columns: id, title and created_on. When you omit the date or time value in the INSERT statement, MySQL inserts the current date and time into the column whose default value is NOW(). You can use the NOW() function to provide a default value for a DATETIME or TIMESTAMP column. Try It Out Using MySQL NOW() function to provide the default value for a column ( NOW() + INTERVAL 1 DAY) 'NOW + 1 day' Code language: SQL (Structured Query Language) ( sql ) The following statement returns the current date and time, now minus 1 day and now plus 1 day: - mysql now minus 1 day SELECT ( NOW() - INTERVAL 1 DAY) 'NOW - 1 day', mysql now plus 1 hour NOW() + INTERVAL 1 HOUR 'NOW + 1 hour' Code language: SQL (Structured Query Language) ( sql ) The following statement returns the current date and time, now minus 1 hour and now plus 1 hour: - mysql now minus 1 hour SELECT ( NOW() - INTERVAL 1 HOUR) 'NOW - 1 hour', If you want to change the MySQL server’s time zone to adjust the current date and time returned by the NOW() function, you use the following statement: SET time_zone = your_time_zone Code language: SQL (Structured Query Language) ( sql ) MySQL NOW() function calculationsīecause the NOW() function returns a number when it is used in a numeric context, you can use it in calculations e.g., now plus 1 hour, now minus 1 hour, and now plus 1 day. If you want to get exact time at which the statement executes, you need to use SYSDATE() instead see the following example: SELECT SYSDATE(), SLEEP( 5), SYSDATE() Code language: SQL (Structured Query Language) ( sql ) ![]() However, both NOW() functions return the same value though they executed at different times. In the query, the first NOW() function executed, and the SLEEP(5) function paused the execution of the query for 5 seconds, and the second NOW() function executed. See the following example: SELECT NOW(), SLEEP( 5), NOW() Code language: SQL (Structured Query Language) ( sql ) Notice that the NOW() function returns a constant date and time at which the statement started executing. However, in the numeric context as the following example, the NOW() function returns the current date and time as a number: SELECT NOW() + 0 Code language: SQL (Structured Query Language) ( sql ) For example, in the following statement, the NOW() function returns the current date and time as a string: SELECT NOW() Code language: SQL (Structured Query Language) ( sql ) The returned type of the NOW() function depends on the context where it is used. ![]() The MySQL NOW() function returns the current date and time in the configured time zone as a string or a number in the 'YYYY-MM-DD HH:MM:DD' or 'YYYYMMDDHHMMSS.uuuuuu' format. Summary: in this tutorial, you will learn about the MySQL NOW() function and apply the NOW function in various contexts.
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