How to query non-null data in oracle database

You can query the Oracle database for non-null data by filtering the data in the WHERE clause using the NOT NULL condition. Sample query: SELECT name FROM employee WHERE name IS NOT NULL;

How to query data that is not empty in Oracle database

To query non-null data in the Oracle database, you can use the NOT NULL condition.

Syntax:

<code class="sql">SELECT column_name(s)
FROM table_name
WHERE column_name IS NOT NULL;</code>

Example:

Query the name column data that is not empty:

<code class="sql">SELECT name
FROM employee
WHERE name IS NOT NULL;</code>

Detailed explanation:

• SELECT statement is used to select the columns to be queried.
• FROM Specify the data table to be queried. The
• WHERE clause is used to filter the results and only return rows that meet certain conditions.
• IS NOT NULL Condition checks whether the column is not empty.

Additional points:

• For numeric type columns, NULL values ​​will be represented as NULL , instead of 0 or other default values.
• You can use the NOT NULL constraint to enforce that the column cannot be null in the table definition.

By using the NOT NULL condition, you can easily identify and obtain data that is not null in an Oracle database.

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