---
warning: DO NOT CHANGE THIS MANUALLY, THIS IS GENERATED BY https://github.com/duckdb/community-extensions repository, check README there
title: dryrun
excerpt: |
  DuckDB Community Extensions
  Estimate Parquet scan bytes for SELECT queries without executing them

extension:
  name: dryrun
  description: Estimate Parquet scan bytes for SELECT queries without executing them
  version: 0.1.1
  language: C++
  build: cmake
  license: MIT
  maintainers:
    - aleda145

repo:
  github: aleda145/duckdb-dryrun
  ref: 0bddce4a16696198a282282879f10c4904de8570

docs:
  hello_world: |
    SELECT *
    FROM dryrun(
      'SELECT * FROM ''https://dryrun-data.dahl.dev/gaia-5m.parquet'''
    );
  extended_description: |
    Dryrun adds a table function for estimating Parquet scan
    bytes before running a query.

    It parses a read-only SELECT statement, finds explicit Parquet scan
    sources, determines required columns, uses Parquet metadata for
    compressed column-chunk sizes, and applies simple
    row-group pruning from min/max statistics when possible.

    The result reports estimated data bytes, estimated Parquet metadata
    bytes, files, row groups used versus total row groups, confidence, and
    notes (if any).

extension_star_count: 0
extension_star_count_pretty: 0
extension_download_count: 525
extension_download_count_pretty: 525
image: '/images/community_extensions/social_preview/preview_community_extension_dryrun.png'
layout: community_extension_doc
---
### Compatibility Matrix

This table covers all DuckDB releases that have not reached [end-of-life](https://duckdb.org/release_calendar), including LTS releases, and shows the 2 most recent patch releases of each. Older patch releases are not listed, but the extension may be available for them as well.

<div class="extension_compatibility_table"></div>

| Platform | 1.4.4 | 1.4.5 | 1.5.5 | 1.5.6 | 2.0.0 |
| :--- | :---: | :---: | :---: | :---: | :---: |
| Linux AMD64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| Linux ARM64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| macOS AMD64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| macOS ARM64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| Windows AMD64 | ❌ | ❌ | ❌ | ❌ | ✅ |
| Windows ARM64 | ❌ | ❌ | ❌ | ❌ | ❌ |
| WebAssembly | ❌ | ❌ | ❌ | ❌ | ✅ |

### Installing and Loading
```sql
INSTALL {{ page.extension.name }} FROM community;
LOAD {{ page.extension.name }};
```

{% if page.docs.hello_world %}
### Example
```sql
{{ page.docs.hello_world }}```
{% endif %}

{% if page.docs.extended_description %}
### About {{ page.extension.name }}
{{ page.docs.extended_description }}
{% endif %}
### Added Functions

<div class="extension_functions_table"></div>

| function_name | function_type | description | comment | examples |
|---------------|---------------|-------------|---------|----------|
| dryrun        | table         | NULL        | NULL    |          |

### Overloaded Functions

<div class="extension_functions_table"></div>

This extension does not add any function overloads.

### Added Types

<div class="extension_types_table"></div>

This extension does not add any types.

### Added Settings

<div class="extension_settings_table"></div>

|      name      |                       description                       | input_type | scope  | aliases | typed_value |
|----------------|---------------------------------------------------------|------------|--------|---------|-------------|
| temp_directory | Set the directory to which temporary files are written. | VARCHAR    | GLOBAL | []      | post.db.tmp |