Build Your Own DatabaseDriven Website Using PHP amp;amp; MySQL [Electronic resources] نسخه متنی

DATE

Description: A date.

Range: '1000-01-01' to '9999-12-31',
and '0000-00-00'

Storage space: 3 bytes (24 bits)

TIME

Description: A time.

Range: '-838:59:59' to '838:59:59'

Storage space: 3 bytes (24 bits)

DATETIME

Description: A date and time.

Range: '1000-01-01 00:00:00' to '9999-12-31
23:59:59'

Storage space: 8 bytes (64 bits)

YEAR

Description: A year.

Range: 1901 to 2155, and 0000

Storage space: 1 byte (8 bits)

Notes: You can specify a year value
with a four-digit number (1901 to 2155,
or 0000), a 4-digit string ('1901' to '2155',
or '0000'), a two-digit number (70 to 99 for
1970 to 1999, 1 to 69 for 2001 to 2069,
or 0 for 0000), or a two-digit string ('70' to '99' for
1970 to 1999, '00' to '69' for 2000
to 2069). Note that you cannot specify the year 2000 with a two-digit number,
and you can't specify the year 0000 with a two-digit string. Invalid year
values are always converted to 0000.

TIMESTAMP[(M)]

Description: A timestamp (date/time),
in YYYYMMDDHHMMSS format.

Range: 19700101000000 to
sometime in 2037 on current systems.

Storage space: 4 bytes (32 bits)

Notes: An INSERT or UPDATE operation
on a row that contains one or more TIMESTAMP columns will
automatically update the first TIMESTAMP column in the
row with the current date/time. This lets you use such a column as the 'last
modified date/time' for the row. Assigning a value of NULL to
the column will have the same effect, thereby providing a means of 'touching'
the date/time. You can also assign actual values as you would for any other
column.

Allowable values for M are 14, 12, 10, 8, 6, 4, and
2, and correspond to the display formats YYYYMMDDHHMMSS, YYMMDDHHMMSS, YYMMDDHHMM, YYYYMMDD, YYMMDD, YYMM, and YY respectively.
Odd values from 1 to 13 will automatically be bumped up to the next even number,
while values of 0 or greater than 14 are changed to 14.