# covar_pop

> For the complete documentation index, see [llms.txt](https://docs.redpanda.com/llms.txt). Component-specific: [cloud-data-platform-full.txt](https://docs.redpanda.com/cloud-data-platform-full.txt)

---
title: covar_pop
latest-operator-version: v26.1.4
latest-console-tag: v3.7.3
latest-connect-version: 4.93.0
latest-redpanda-tag: v26.1.9
docname: sql/sql-functions/aggregate-functions/statistics/covar-pop
page-component-name: cloud-data-platform
page-version: master
page-component-version: master
page-component-title: Cloud
page-relative-src-path: sql/sql-functions/aggregate-functions/statistics/covar-pop.adoc
page-edit-url: https://github.com/redpanda-data/cloud-docs/edit/main/modules/reference/pages/sql/sql-functions/aggregate-functions/statistics/covar-pop.adoc
description: The `covar_pop()` aggregate function calculates the population covariance between two sets of number pairs.
page-topic-type: reference
page-git-created-date: "2026-05-26"
page-git-modified-date: "2026-05-26"
---

<!-- Source: https://docs.redpanda.com/cloud-data-platform/reference/sql/sql-functions/aggregate-functions/statistics/covar-pop.md -->

The `covar_pop()` aggregate function calculates the population covariance between two sets of number pairs. This function measures how much two variables change together, providing insight into their linear relationship.

## [](#syntax)Syntax

The syntax for this function is:

```sql
COVAR_POP(y, x)
```

## [](#parameters)Parameters

-   `y`: Variable being predicted.

-   `x`: Variable used for prediction.


## [](#examples)Examples

The following example uses a simplified version of the `film` table from the Pagila database, containing only the `title`, `length` and `rating` columns. The complete schema for the `film` table can be found on the [Pagila](https://www.postgresql.org/ftp/projects/pgFoundry/dbsamples/pagila/pagila/) database website.

```sql
DROP TABLE IF EXISTS film;
CREATE TABLE film (
  title text NOT NULL,
  length int,
  rating int
);
INSERT INTO film(title, length, rating) VALUES
  ('ATTRACTION NEWTON', 83, 5),
  ('CHRISTMAS MOONSHINE', 150, 7),
  ('DANGEROUS UPTOWN', 121, 4),
  ('KILL BROTHERHOOD', 54, 3),
  ('HALLOWEEN NUTS', 47, 5),
  ('HOURS RAGE', 122, 7),
  ('PIANIST OUTFIELD', 136, 7),
  ('PICKUP DRIVING', 77, 3),
  ('INDEPENDENCE HOTEL', 157, 7),
  ('PRIVATE DROP', 106, 4),
  ('SAINTS BRIDE', 125, 3),
  ('FOREVER CANDIDATE', 131, 7),
  ('MILLION ACE', 142, 5),
  ('SLEEPY JAPANESE', 137, 4),
  ('WRATH MILE', 176, 7),
  ('YOUTH KICK', 179, 7),
  ('CLOCKWORK PARADISE', 143, 5);
```

The following query uses the `covar_pop()` function to calculate the covariance between film length and rating:

```sql
SELECT
    COVAR_POP(length, rating) AS Covariance
FROM film;
```

The query returns:

```sql
    covariance
-------------------
 36.02768166089963
(1 row)
```