# Expect\_column\_values\_to\_be\_in\_set not counting null values as unexpected in GX 1.3.1

**URL:** https://discourse.greatexpectations.io/t/expect-column-values-to-be-in-set-not-counting-null-values-as-unexpected-in-gx-1-3-1/2180
**Category:** GX Core Support
**Created:** [April 11, 2025, 6:58am UTC](https://discourse.greatexpectations.io/t/expect-column-values-to-be-in-set-not-counting-null-values-as-unexpected-in-gx-1-3-1/2180 "2025-04-11T06:58:52Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![Jyoti\_Thakkar](https://avatars.discourse-cdn.com/v4/letter/j/6f9a4e/32.png) [@Jyoti\_Thakkar](https://discourse.greatexpectations.io/u/Jyoti_Thakkar)
#### Post date: [April 11, 2025, 6:58am UTC](https://discourse.greatexpectations.io/t/expect-column-values-to-be-in-set-not-counting-null-values-as-unexpected-in-gx-1-3-1/2180/1 "2025-04-11T06:58:52Z")

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I’m using **Great Expectations v1.3.1** with the **Fluent (Validator-based)** API to validate a simple rule:

> Check if all values in a column are equal to `"mango"` using `expect_column_values_to_be_in_set`.

Here’s what I noticed:

- When the column contains `null` (None/NaN) values, **they are not being counted as unexpected**.
- I expect `null` values to be treated as failures

Any guidance or workarounds would be appreciated!