## Syntax
```mermaid
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flowchart TD
stdDevAggregateFunction_start((START))
stdDevAggregateFunction_start --> stdDevAggregateFunction_0_0[STDDEV]:::quoted
stdDevAggregateFunction_0_0 --> stdDevAggregateFunction_0_1["("]:::quoted
stdDevAggregateFunction_0_1 --> stdDevAggregateFunction_0_2[DISTINCT]:::quoted
stdDevAggregateFunction_0_2 --> stdDevAggregateFunction_0_3[<a href="Invantive UniversalSQL/Grammar/Expression" class="internal-link">expression</a>]
stdDevAggregateFunction_0_3 --> stdDevAggregateFunction_0_4[")"]:::quoted
stdDevAggregateFunction_0_4 --> stdDevAggregateFunction_end((END))
```
## Purpose
Group function to find the standard deviation from a group of numerical values.