Can the DATE type in Oracle be empty? Yes, you can use NULL values to represent empty date values.
Can the DATE type in Oracle be empty?
Yes, the DATE type in Oracle can store null value.
Detailed description
Oracle's DATE type represents a date and can store dates from January 1, 4712 BC to December 31, 9999 AD .
To represent empty date values, NULL values can be used. A NULL value indicates that there are no valid values in the column.
Example
The following SQL statement creates a DATE column named "birth_date", which allows NULL values:
CREATE TABLE myTable ( birth_date DATE );
The following SQL statement Insert a date into the "birth_date" column:
INSERT INTO myTable (birth_date) VALUES ('1980-12-31');
The following SQL statement inserts a NULL value into the "birth_date" column:
INSERT INTO myTable (birth_date) VALUES (NULL);
Benefits
allowed The DATE type provides the following benefits for null values:
- Storage of undefined or unknown date values.
- Simplifies data processing because you can avoid using special values (such as "0000-00-00") to represent empty dates.
- Improve query performance because null values will not be included in index or comparison operations.
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