TIMESTAMP
[(fractional_seconds_precision
)]
Year,month,and day values of date,as well as hour,minute,and second values of time,wherefractional_seconds_precision
is the number of digits in the fractional part of theSECOND
datetime field. Accepted values offractional_seconds_precision
are 0 to 9. The default is 6. The default format is determined explicitly by theNLS_TIMESTAMP_FORMAT
parameter or implicitly by theNLS_TERRITORY
parameter. The size is 7 or 11 bytes,depending on the precision. This data type contains the datetime fieldsYEAR
,MONTH
,238);">DAY,238);">HOUR,238);">MINUTE,andSECOND
. It contains fractional seconds but does not have a time zone.
fractional_seconds_precision是秒的小数部分的精度位数,这个精度位数从0到9,默认是6