Can the date type in oracle be empty?

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:

<code class="sql">CREATE TABLE myTable (
  birth_date DATE
);</code>

The following SQL statement Insert a date into the "birth_date" column:

<code class="sql">INSERT INTO myTable (birth_date) VALUES ('1980-12-31');</code>

The following SQL statement inserts a NULL value into the "birth_date" column:

<code class="sql">INSERT INTO myTable (birth_date) VALUES (NULL);</code>

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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