MySQL retrieves and displays TIME values in
'HH:MM:SS' format (or
'HHH:MM:SS' format for large hours values).
TIME values may range from
'-838:59:59' to
'838:59:59'. The hours part may be so large
because the TIME type can be used not only to
represent a time of day (which must be less than 24 hours), but
also elapsed time or a time interval between two events (which
may be much greater than 24 hours, or even negative).
You can specify TIME values in a variety of
formats:
As a string in 'D HH:MM:SS.fraction'
format. You can also use one of the following
“relaxed” syntaxes:
'HH:MM:SS.fraction',
'HH:MM:SS', 'HH:MM',
'D HH:MM:SS', 'D
HH:MM', 'D HH', or
'SS'. Here D
represents days and can have a value from 0 to 34. Note that
MySQL does not store the fraction part.
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, HHMMSS,
HHMMSS.fraction. Note that MySQL does not
store the fraction part.
As the result of a function that returns a value that is
acceptable in a TIME context, such as
CURRENT_TIME.
For TIME values specified as strings that
include a time part delimiter, it is not necessary to specify
two digits for hours, minutes, or seconds values that are less
than 10. '8:3:2' is the
same as '08:03:02'.
Be careful about assigning abbreviated values to a
TIME column. Without colons, MySQL interprets
values using the assumption that the two rightmost digits
represent seconds. (MySQL interprets TIME
values as elapsed time rather than as time of day.) For example,
you might think of '1112' and
1112 as meaning '11:12:00'
(12 minutes after 11 o'clock), but MySQL interprets them as
'00:11:12' (11 minutes, 12 seconds).
Similarly, '12' and 12 are
interpreted as '00:00:12'.
TIME values with colons, by contrast, are
always treated as time of the day. That is,
'11:12' mean '11:12:00',
not '00:11:12'.
By default, values that lie outside the TIME
range but are otherwise legal are clipped to the closest
endpoint of the range. For example,
'-850:00:00' and
'850:00:00' are converted to
'-838:59:59' and
'838:59:59'. Illegal TIME
values are converted to '00:00:00'. Note that
because '00:00:00' is itself a legal
TIME value, there is no way to tell, from a
value of '00:00:00' stored in a table,
whether the original value was specified as
'00:00:00' or whether it was illegal.
For more restrictive treatment of invalid
TIME values, enable strict SQL mode to cause
errors to occur. See Section 5.2.5, “The Server SQL Mode”.
