The DATE, DATETIME, and TIMESTAMP Types any  TIMESTAMP  column to the current date and time by assigning it a  NULL  value, unless it has been defined with the  NULL  attribute to permit  NULL  values. Automatic initialization and updating to the current date and time can be specified using  DEFAULT CURRENT_TIMESTAMP  and  ON UPDATE CURRENT_TIMESTAMP  column definition clauses. By default, the first  TIMESTAMP  column has these properties, as previously noted. However, any  TIMESTAMP column in a table can be defined to have these properties. A time. The range is  ’-838:59:59.000000’  to  ’838:59:59.000000’ . MySQL displays  TIME values in  ’ hh:mm:ss [. fraction ]’  format, but permits assignment of values to  TIME  columns using either strings or numbers. An optional  fsp  value in the range from 0 to 6 may be given to specify fractional seconds precision. A value of 0 signifies that there is no fractional part. If omitted, the default precision is 0. A year in 4-digit format. MySQL displays  YEAR  values in  YYYY  format, but permits assignment of values to  YEAR  columns using either strings or numbers. Values display as  1901  to  2155 , or  0000 . For additional information about  YEAR  display format and interpretation of input values, see Section 11.2.4, “The YEAR Type” . As of MySQL 8.0.19, the  YEAR(4)  data type with an explicit display width is deprecated; you should expect support for it to be removed in a future version of MySQL. Instead, use  YEAR  without a display width, which has the same meaning. MySQL 8.0 does not support the 2-digit  YEAR(2)  data type permitted in older versions of MySQL. For instructions on converting to 4-digit  YEAR , see 2-Digit YEAR(2) Limitations and Migrating to 4-Digit YEAR, in MySQL 5.7 Reference Manual. The  SUM()  and  AVG()  aggregate functions do not work with temporal values. (They convert the values to numbers, losing everything after the first nonnumeric character.) To work around this problem, convert to numeric units, perform the aggregate operation, and convert back to a temporal value. Examples: The  DATE ,  DATETIME , and  TIMESTAMP  types are related. This section describes their characteristics, how they are similar, and how they differ. MySQL recognizes  DATE ,  DATETIME , and  TIMESTAMP  values in several formats, described in Section 9.1.3, “Date and Time Literals” . For the  DATE  and  DATETIME  range descriptions, “supported”  means that although earlier values might work, there is no guarantee. The  DATE  type is used for values with a date part but no time part. MySQL retrieves and displays  DATE values in  ’ YYYY-MM-DD ’  format. The supported range is  ’1000-01-01’  to  ’9999-12-31’ . The  DATETIME  type is used for values that contain both date and time parts. MySQL retrieves and displays  DATETIME  values in  ’ YYYY-MM-DD hh:mm:ss ’  format. The supported range is  ’1000-01-01 00:00:00’  to  ’9999-12-31 23:59:59’ . 11.2.2 The DATE, DATETIME, and TIMESTAMP Types SELECT SEC_TO_TIME(SUM(TIME_TO_SEC( time_col ))) FROM  tbl_name ; SELECT FROM_DAYS(SUM(TO_DAYS( date_col ))) FROM  tbl_name ; •  YEAR[(4)] Note 2024 •  TIME[( fsp )]