Date and Time Literals •As a number in either  YYYYMMDDhhmmss  or  YYMMDDhhmmss  format, provided that the number makes sense as a date. For example,  19830905132800  and  830905132800  are interpreted as ’1983-09-05 13:28:00’ . •Year values in the range  70-99  become  1970-1999 . •Year values in the range  00-69  become  2000-2069 . •As a string in  ’D hh:mm:ss’  format. You can also use one of the following “relaxed”  syntaxes: ’hh:mm:ss’ ,  ’hh:mm’ ,  ’D hh:mm’ ,  ’D hh’ , or  ’ss’ . Here  D  represents days and can have a value from 0 to 34. •As a string with no delimiters in  ’hhmmss’  format, provided that it makes sense as a time. For example, ’101112’  is understood as  ’10:11:12’ , but  ’109712’  is illegal (it has a nonsensical minute part) and becomes  ’00:00:00’ . •As a number in  hhmmss  format, provided that it makes sense as a time. For example,  101112  is understood as  ’10:11:12’ . The following alternative formats are also understood:  ss ,  mmss , or hhmmss . 1864 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 MySQL recognizes  TIME  values in these formats: 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’ . 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. 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’ . See also Section 11.2.8, “2-Digit Years in Dates” . Dates containing two-digit year values are ambiguous because the century is unknown. MySQL interprets two-digit year values using these rules: 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 11.2.6, “Fractional Seconds in Time Values” .