标准 SQL 需要使用类型关键字和字符串指定时间文字。关键字和字符串之间的空格是可选的。

DATE 'str'
TIME 'str'
TIMESTAMP 'str'

MySQL 可以识别，但与标准 SQL 不同，它不需要 type 关键字。符合标准的应用程序应该包括时间文字的类型关键字。

MySQL 还识别与标准 SQL 语法相对应的 ODBC 语法：

{ d 'str' }
{ t 'str' }
{ ts 'str' }

MySQL 使用类型关键字和 ODBC 构造分别生成DATE、 TIME和 DATETIME值，如果指定，包括尾随的小数秒部分。该 TIMESTAMP语法 DATETIME在 MySQL 中生成一个值，因为 DATETIME其范围更接近于标准 SQL TIMESTAMP类型，其年份范围从0001到 9999. （MySQL TIMESTAMP年份范围是 1970到2038。）

MySQL 识别DATE这些格式的值：

MySQL recognizes DATETIME and TIMESTAMP values in these formats:

A DATETIME or TIMESTAMP value can include a trailing fractional seconds part in up to microseconds (6 digits) precision. The fractional part should always be separated from the rest of the time by a decimal point; no other fractional seconds delimiter is recognized. For information about fractional seconds support in MySQL, see Section 11.2.7, “Fractional Seconds in Time Values”.

Dates containing two-digit year values are ambiguous because the century is unknown. MySQL interprets two-digit year values using these rules:

See also Section 11.2.9, “2-Digit Years in Dates”.

For values specified as strings that include date part delimiters, it is unnecessary to specify two digits for month or day values that are less than 10. '2015-6-9' is the same as '2015-06-09'. Similarly, for values specified as strings that include time part delimiters, it is unnecessary to specify two digits for hour, minute, or second values that are less than 10. '2015-10-30 1:2:3' is the same as '2015-10-30 01:02:03'.

Values specified as numbers should be 6, 8, 12, or 14 digits long. If a number is 8 or 14 digits long, it is assumed to be in YYYYMMDD or YYYYMMDDhhmmss format and that the year is given by the first 4 digits. If the number is 6 or 12 digits long, it is assumed to be in YYMMDD or YYMMDDhhmmss format and that the year is given by the first 2 digits. Numbers that are not one of these lengths are interpreted as though padded with leading zeros to the closest length.

Values specified as nondelimited strings are interpreted according their length. For a string 8 or 14 characters long, the year is assumed to be given by the first 4 characters. Otherwise, the year is assumed to be given by the first 2 characters. The string is interpreted from left to right to find year, month, day, hour, minute, and second values, for as many parts as are present in the string. This means you should not use strings that have fewer than 6 characters. For example, if you specify '9903', thinking that represents March, 1999, MySQL converts it to the “zero” date value. This occurs because the year and month values are 99 and 03, but the day part is completely missing. However, you can explicitly specify a value of zero to represent missing month or day parts. For example, to insert the value '1999-03-00', use '990300'.

MySQL recognizes TIME values in these formats:

A trailing fractional seconds part is recognized in the 'D hh:mm:ss.fraction', 'hh:mm:ss.fraction', 'hhmmss.fraction', and hhmmss.fraction time formats, where fraction is the fractional part in up to microseconds (6 digits) precision. The fractional part should always be separated from the rest of the time by a decimal point; no other fractional seconds delimiter is recognized. For information about fractional seconds support in MySQL, see Section 11.2.7, “Fractional Seconds in Time Values”.

对于TIME指定为包含时间部分定界符的字符串的值，无需为小于 的小时、分钟或秒值指定两位数10。 '8:3:2'与 相同 '08:03:02'。