直接看官網文檔 ：
https://dev.mysql.com/doc/refman/8.0/en/date-and-time-functions.html#function_date-format
| Specifier | Description |
|---|---|
%a |
Abbreviated weekday name (Sun..Sat) |
%b |
Abbreviated month name (Jan..Dec) |
%c |
Month, numeric (0..12) |
%D |
Day of the month with English suffix (0th, 1st, 2nd, 3rd, …) |
%d |
Day of the month, numeric (00..31) |
%e |
Day of the month, numeric (0..31) |
%f |
Microseconds (000000..999999) |
%H |
Hour (00..23) |
%h |
Hour (01..12) |
%I |
Hour (01..12) |
%i |
Minutes, numeric (00..59) |
%j |
Day of year (001..366) |
%k |
Hour (0..23) |
%l |
Hour (1..12) |
%M |
Month name (January..December) |
%m |
Month, numeric (00..12) |
%p |
AM or PM |
%r |
Time, 12-hour (hh:mm:ss followed by AM or PM) |
%S |
Seconds (00..59) |
%s |
Seconds (00..59) |
%T |
Time, 24-hour (hh:mm:ss) |
%U |
Week (00..53), where Sunday is the first day of the week; WEEK() mode 0 |
%u |
Week (00..53), where Monday is the first day of the week; WEEK() mode 1 |
%V |
Week (01..53), where Sunday is the first day of the week; WEEK() mode 2; used with %X |
%v |
Week (01..53), where Monday is the first day of the week; WEEK() mode 3; used with %x |
%W |
Weekday name (Sunday..Saturday) |
%w |
Day of the week (0=Sunday..6=Saturday) |
%X |
Year for the week where Sunday is the first day of the week, numeric, four digits; used with %V |
%x |
Year for the week, where Monday is the first day of the week, numeric, four digits; used with %v |
%Y |
Year, numeric, four digits |
%y |
Year, numeric (two digits) |
%% |
A literal % character |
% |
x, for any “x” not listed above |
裏面有1個%f，但是是6位的，如果毫秒只需要3位，再套一層substring，效果如下：
上圖也順便給了另1個小技巧：默認情況下now()和current_timestamp()函數，只精確到秒，如果需要到毫秒，傳入3或6這樣的精度值即可。