Posted by Hello friends, in this article, I will talk to you about the usage of the SQL ISNULL function.
The ISNULL function comes into play when we want to perform operations on a specified column that may have a NULL value. For example, let’s say we want to perform an addition operation, concatenating string values from two columns. If one of the columns has a NULL value and we don’t use the ISNULL function, the result will be NULL even if only one of the two columns has a NULL value. Similarly, if we are dealing with an INT column and want to perform a calculation, the result will be NULL if the column’s value is NULL, preventing the desired operation.
In the usage of the ISNULL function, if the column value is NULL, it allows us to specify a default value, perform the necessary calculations, and ensures that it does not return a NULL value.
How to Use the ISNULL Function?
The ISNULL function takes two parameters. The first one is the column we want to handle, and the second parameter is the value we want to replace if the specified column is NULL. By providing the desired replacement value as the second parameter, we can effectively manage this operation.
If we go through an example:
SELECT ProductName, ISNULL(Price, 0) FROM Products
In the example above, we ensure that if the Price field is NULL for a product, it will be displayed as zero (0).
As you can see, folks, you can use the ISNULL function as shown above.
I hope, this article is helpful.
See you in the next article…