# FUNNELSTEPDURATIONSTATS

Computes step-to-step duration statistics for window funnel matches.

## Signature

> `FUNNELSTEPDURATIONSTATS(timestampExpression, windowSize, numberSteps, stepExpression1, ..., stepExpressionN, 'durationFunctions=...' [, 'mode=...' | 'strict_order' | 'strict_deduplication' | 'strict_increase' | 'keep_all' | 'maxStepDuration=...'])`

## Parameters

| Parameter                             | Description                                                                                                                                                                                                            |
| ------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `timestampExpression`                 | Expression that evaluates to the event timestamp. Pinot accepts `TIMESTAMP` or `LONG` values.                                                                                                                          |
| `windowSize`                          | Positive time window literal. Funnel steps must complete within this window.                                                                                                                                           |
| `numberSteps`                         | Number of funnel steps. This must match the number of step expressions that follow.                                                                                                                                    |
| `stepExpression1 ... stepExpressionN` | Boolean expressions that define each funnel step in order.                                                                                                                                                             |
| `'durationFunctions=...'`             | Required config string listing the statistics to emit. Supported values are `COUNT`, `AVG`, `MIN`, `MEDIAN`, `MAX`, and `PERCENTILE<value>` such as `PERCENTILE95`. The output preserves the requested function order. |
| Optional trailing arguments           | Optional funnel controls shared with the other window funnel functions, including `mode=...`, `strict_order`, `strict_deduplication`, `strict_increase`, `keep_all`, and `maxStepDuration=...`.                        |

## Returns

Returns a `DOUBLE[]` flattened in step order.

For each step, Pinot emits the requested statistics in the same order they were listed in `durationFunctions`. If `COUNT` is requested, Pinot includes it for every step. Duration metrics on the final step use Pinot's double null placeholder because there is no next step to measure against.

If `COUNT` is omitted and no funnel completes, Pinot returns an empty array.

## Example

```sql
SELECT
  userId,
  funnelStepDurationStats(
    timestampCol,
    '1000',
    4,
    url = '/product/search',
    url = '/cart/add',
    url = '/checkout/start',
    url = '/checkout/confirmation',
    'durationFunctions=count,avg,min,median,percentile95,max'
  ) AS statsArray
FROM events
GROUP BY userId
HAVING arrayLength(statsArray) > 0
ORDER BY userId
```

In Pinot's integration tests, a completed four-step funnel with 10-millisecond gaps between steps returns duration stats such as:

* step 0 -> step 1: `count=1`, `avg=10`, `min=10`, `median=10`, `percentile95=10`, `max=10`
* step 1 -> step 2: the same six values
* step 2 -> step 3: the same six values

For more information on the related funnel functions, see [Funnel Analysis Functions](/functions/funnel.md).


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://docs.pinot.apache.org/functions/aggregation/funnelstepdurationstats.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.