> For the complete documentation index, see [llms.txt](https://200ok.gitbook.io/200ok-documents/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://200ok.gitbook.io/200ok-documents/user-manual/built-in-functions/logical/isnull.md).
# isNull
isNull() function is the Standard function available in 200OK.
**Description** : The isNull function checks whether an expression is null and returns TRUE or FALSE accordingly.
**Syntax** : fx\_isNull(expression)
**Example** : fx\_isNull(null) returns true, while fx\_isNull(10>11) returns false.
\
Here we go with simple scenario using the above function.
**Scenario** : In a database query, a software developer is validating data retrieved from a database before further processing. They utilize a function to check if the retrieved data is null. If the data is null, the system handles it differently than if it contains valid information.
**Request Side** :
**Response Side** :
