# STDDEVPOP

Returns the population standard deviation of values in a group as `Double`. This is the square root of the population variance.

## Signature

> STDDEVPOP(colName)

## Usage Examples

These examples are based on the [Batch Quick Start](/start-here/quick-start.md#batch-processing).

```sql
select STDDEVPOP(hits) AS value
from baseballStats
WHERE hits > 0
```

| value    |
| -------- |
| 35.13642 |


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