How to convert string to datetime type in mysql
Two conversion methods: 1. Use the str_to_date() function to format a string and convert it into a date and time value according to the specified format. The syntax is "str_to_date (string value, conversion format)". 2. Use the CAST() function to convert the specified string value to the datetime data type, the syntax is "CAST (string value AS datetime)".
The operating environment of this tutorial: windows7 system, mysql8 version, Dell G3 computer.
MySQL DATETIME type
The DATETIME type is used for values that need to contain both date and time information, and requires 8 bytes for storage. The date format is 'YYYY-MM-DD HH:MM:SS', where YYYY represents the year, MM represents the month, DD represents the day, HH represents the hour, MM represents the minute, and SS represents the second.
MySQL method of converting string to datetime type
Method 1: Use str_to_date() function
str_to_date() is a specialized string to date function that can convert a string into a date and time value.
str_to_date(str, format)
str: Required. A string to be formatted as a date
format: Required. The format to use. Can be one or a combination of the following values:
format format | description |
---|---|
%a | Abbreviated name of working day (Sunday to Saturday) |
%b | Abbreviated name of month (January to December) |
%C | Numeric month name (0 to 12) |
%D | Month as numeric value A certain day in , followed by the suffix (1st, 2nd, 3rd,...) |
%d | as the month date of the value (01 to 31) |
%e | a day of the month as a value (0 to 31) |
%f | Microseconds (000000 to 999999) |
%H | Hours (00 to 23) |
%h | Hours (00 to 12) |
%I | Hours (00 to 12) |
%i | Minutes (00 to 59) |
%j | Day of the Year (001 to 366) |
%k | Hours (0 to 23) |
%l | Hours (1 to 12) |
%M | Month name (January to December) |
Month name as numerical value ( 00 to 12) | |
AM or PM | |
Time is 12 Hour AM or PM format (hh:mm:ss AM/PM) | |
Seconds (00 to 59) | |
Seconds (00 to 59) | |
Time in 24-hour format (hh:mm:ss) | |
Sunday is the first day of the week (00 to 53) | |
Monday is the first day of the week (00 to 53) | |
Sunday is the first day of the week (01 to 53) week. Used with %X | |
Monday is the first day of the week (01 to 53). Use with %X | |
Weekday Name All (Sunday to Saturday) | |
Sunday = 0 and Saturday = 6 for the day of the week | |
Sunday is the first day of the week. Used with %V | |
Monday is the first day of the week. Used with %V | |
Year is a number, 4-digit value | |
The year is a number, a 2-digit value |
SELECT STR_TO_DATE('21,5,2022','%d,%m,%Y');
SELECT STR_TO_DATE("2022,6,14 10,40,10", "%Y,%m,%d %h,%i,%s");
The CAST() function is used for type conversion to convert a value (of any type) to a specified data type.
Syntax for converting string to datetime type
CAST(字符串值 AS datetime)
Example:
SELECT CAST("2008.08.09 08:09:30" AS DATETIME);
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