---
title: Python analysis
description: Attach a Python script to a report to run forecasting, regression, cohort, and other analysis that SQL can't express, and save the result as a re-runnable report.
---

<Warning>

Python analysis is currently in preview, and the user experience and the script
contract may still change. Reach out to the [Cube support
team](/admin/account-billing/support) to activate this feature for your account.

</Warning>

A report can carry an attached **Python script** that transforms the report's SQL
result. The report's chart then renders the script's **output** instead of the raw
SQL rows. This turns an analysis that would otherwise scroll away in a chat
transcript into a saved, re-runnable, shareable report.

Use it for work SQL can't express — forecasting, regression, cohort analysis,
statistical tests, clustering, and anomaly detection.

<Frame>
  <img src="https://static.cube.dev/docs/explore-analyze/workbooks/python-analysis/code-panel-forecast.png" alt="A workbook report with the Python code panel open, showing a Prophet forecast script above a chart plotting actual monthly orders alongside the forecast and its confidence interval" />
</Frame>

## Adding Python to a report

### From Analytics Chat

Ask for the analysis in natural language — "forecast next quarter's revenue",
"find anomalies in signups" — and the agent runs Python for you, rendering the
result inline in the [chat thread](/docs/explore-analyze/analytics-chat). This
result is ephemeral by default.

Ask to **save it to a workbook** and Cube persists both the code and the run result
onto a report, which then renders the saved output without re-running. Saving
re-executes the analysis.

<Info>

The agent reaches for Python **only** when the answer genuinely needs a statistics
or machine-learning library. Ordinary aggregations, top-N, ratios, running totals,
period-over-period comparisons, and time series all stay in SQL, because a Python
run costs a re-query plus a sandbox start. If you expected Python and got a plain
SQL report, that is usually correct behavior.

</Info>

### From the toolbar

Workbooks and [Explore](/docs/explore-analyze/explore) share the same flow.

Click **Python** in the toolbar to open the Python panel, then **Add script** to
attach one. Cube seeds a starter script and opens it on the **Script** tab.
Opening the panel does not attach anything by itself — only **Add script** does.

**Remove**, in the panel header, detaches the script, after which the report
behaves like any SQL-backed one again.

Attaching Python clears any existing SQL result: a python-backed report renders its
last Python run, and a freshly attached script has none until you press **Run**.

Attaching Python in Explore is only available on a **saved** exploration. On an
unsaved one the **Python** button is disabled with the tooltip *"Save the
exploration to add Python"* — **Run** executes server-persisted code, so the
analysis needs a saved report to live on.

## Writing the script

The script runs in a sandbox against a fixed contract:

- Input data arrives as `data.csv` in the working directory.
- Write results to `output.json` as a **flat JSON array of row objects**, for
  example `[{"month": "2026-01", "value": 1.5}, ...]`.

A top-level dict or object is rejected — flatten any nested structure into one
array of uniform rows.

{/* TODO: screenshot — the Python panel's Add script button */}

## Python environment

Every run gets a fresh, isolated sandbox running **Python 3.11**. It is created for
the run and destroyed when the run finishes — nothing carries over between runs.

These packages are pre-installed, along with their dependencies:

| Package | Use |
| --- | --- |
| `pandas`, `numpy` | Dataframes and numerical computing |
| `scipy` | Statistical tests, optimization, interpolation |
| `scikit-learn` | Regression, classification, clustering, anomaly detection |
| `statsmodels` | ARIMA, exponential smoothing, econometric models |
| `prophet` | Time series forecasting with seasonality and holidays |
| `matplotlib`, `seaborn`, `plotly` | Plotting |

Figures are not a supported output. The report's chart is built from `output.json`, and
anything a script writes to disk is discarded with the sandbox — so the plotting
libraries are importable, but a saved figure has nowhere to go.

<Info>

Installing your own packages is not supported yet. Because the sandbox is recreated
for every run, anything a script installs is discarded when the run ends. Support for
adding packages to the environment is coming.

</Info>

## Running and refreshing

The panel's **Script** tab is editable in place, with line numbers. **Reset**
restores the starter template.

- **Edits do not run anything.** They save with the report, and the rendered result
  keeps showing the previous run.
- When the code or its input SQL has changed since the last run, the result is
  marked **Outdated**, with the tooltip *"The Python code or its input SQL changed
  after the last run. Run to refresh the saved result."*
- **Run** executes the stored script in the sandbox and persists the refreshed
  result.
- The **Output** tab shows what the last run printed — the script's stdout and
  stderr, so `print()` is how you inspect intermediate values. Both are captured up
  to the cap in [Limits](#limits), so a chatty script gets truncated.
- The **input SQL panel is read-only** on a python report: that SQL is the
  sandbox's input, not what gets charted. It still offers the **Semantic SQL** and
  **Generated SQL** tabs, both derived from that input query.
- **A failed run keeps the previous chart.** The error surfaces alongside the last
  successful result, which stays rendered.

**Run is the only way the saved result changes.** Opening the report, reloading the
page, or viewing a dashboard never re-runs anything on its own.

{/* TODO: screenshot — the code panel showing the Outdated tag */}

## On dashboards

Python reports render their **saved output** on dashboards. Nothing re-runs on
dashboard load, so a dashboard full of Python reports costs no compute to open —
each widget shows whatever the last **Run** produced.

A python widget can be opened in [Explore](/docs/explore-analyze/explore) from a
dashboard and run from there.

## Who the analysis runs as

<Warning>

Python runs with the **security context of the person who pressed Run** — or of the
chat user who saved the analysis. The result is then persisted on the report, and
**anyone who can view the workbook can see it**.

Row-level security is applied at **run time**, not at view time. A user with broad
access can Run, and the stored output is then readable by people whose own access
is narrower.

</Warning>

Take this into account when deciding who can run and publish Python reports, the
same way you would for any other saved result shared through a workbook.

## Limits

| Limit | Value |
| --- | --- |
| SQL query timeout | 120s |
| Python execution timeout | 120s |
| Maximum output rows persisted | 10,000 |
| Maximum output size | 2 MB |
| stdout/stderr captured | 16 KB |

Exceeding the output caps means the analysis still returns in chat but **cannot be
saved to a report**. Aggregate or summarize inside the script so the output stays
within the caps — analysis results such as forecasts, cohorts, and test statistics
are small by nature.

## Learn more

- [Analytics Chat](/docs/explore-analyze/analytics-chat) — the standalone
  conversational analytics experience
- [Workbook Agent](/docs/explore-analyze/workbooks/workbook-agent) — the authoring
  assistant inside a workbook
- [Source SQL tabs](/docs/explore-analyze/workbooks/source-sql-tabs) — query
  connected data sources directly
