How to Find Records with Null in a Column in SQL
When you need to find records with null values in a particular column of your database in SQL, use the IS NULL operator. This operator takes a single argument, which is the column you want to check for null values. For example, if you wanted to find records with null values in the name column of your database, you would use the following query:
SELECT * FROM table_name WHERE name IS NULL;
Examples
Let's look at a few examples of how this operator can be used. Suppose you have a table called users with the following data:
name | age |
---|---|
John | 25 |
Jane | 30 |
John | 25 |
Bob | 20 |
NULL | 30 |
If you wanted to find records with null values in the name column, you would use the following query:
SELECT * FROM users WHERE name IS NULL;
This query would return the result NULL 30, since there is one record with a null value in the name column.
Additional Info
The IS NULL operator is supported by most major databases, including MySQL, PostgreSQL, and SQL Server. However, the syntax may vary slightly depending on the database you are using. For more information, check out the documentation for your particular database.