SQL date and time data types are collectively called datetime values. The SQL data types for dates, times, and timestamps are listed here. Be aware that columns of these data types may contain data ...

Oracle Rdb has a special value that is called NULL, which signifies an absence of information and is analogous to the SAS System's missing value. By default, columns allow NULL values. Columns can be ...

Null means "undefined" in SQL, so numerous online services don't think Christopher Null exists. ... "Allowing NULL values makes you work extra hard to get the kind of data you are looking for.