> ## Documentation Index > Fetch the complete documentation index at: https://private-7c7dfe99-fix-nav-issues.mintlify.site/llms.txt > Use this file to discover all available pages before exploring further. > Run analytics queries on ClickHouse right from PostgreSQL without rewriting any SQL # pg_clickhouse reference documentation

Introduction

[pg\_clickhouse][pg_clickhouse], an open-source PostgreSQL extension, runs analytics queries on ClickHouse right from PostgreSQL without rewriting any SQL. It supports PostgreSQL 13 and later and ClickHouse v23 and later. Once [ClickPipes](/integrations/clickpipes/home) starts syncing data ClickHouse, use pg\_clickhouse to quickly and easily [import foreign tables] into a PostgreSQL schema. Then run your existing PostgreSQL queries to against those tables, preserving your existing code base while pushing execution down to ClickHouse.

Getting started

The simplest way to try pg\_clickhouse is the [Docker image], which contains the standard PostgreSQL Docker image with the pg\_clickhouse and [re2] extensions: ```sh theme={null} docker run --name pg_clickhouse -e POSTGRES_PASSWORD=my_pass \ -d ghcr.io/clickhouse/pg_clickhouse:19 docker exec -it pg_clickhouse psql -U postgres -c 'CREATE EXTENSION pg_clickhouse' ``` See the [tutorial] to get started importing ClickHouse tables and pushing down queries.

Test case: TPC-H

This table compares [TPC-H] query performance between regular PostgreSQL tables and pg\_clickhouse connected to ClickHouse, both loaded at scaling factor 1; ✔︎ indicates full pushdown, while a dash indicates a query cancellation after 1m. All tests run on a MacBook Pro M4 Max with 36 GB of memory. | Query | PostgreSQL | pg\_clickhouse | Pushdown | | ----------: | ---------: | -------------: | :------: | | \[Query 1] | 4693 ms | 268 ms | ✔︎ | | \[Query 2] | 458 ms | 3446 ms | | | \[Query 3] | 742 ms | 111 ms | ✔︎ | | \[Query 4] | 270 ms | 130 ms | ✔︎ | | \[Query 5] | 337 ms | 1460 ms | ✔︎ | | \[Query 6] | 764 ms | 53 ms | ✔︎ | | \[Query 7] | 619 ms | 96 ms | ✔︎ | | \[Query 8] | 342 ms | 156 ms | ✔︎ | | \[Query 9] | 3094 ms | 298 ms | ✔︎ | | \[Query 10] | 581 ms | 197 ms | ✔︎ | | \[Query 11] | 212 ms | 24 ms | | | \[Query 12] | 1116 ms | 84 ms | ✔︎ | | \[Query 13] | 958 ms | 1368 ms | | | \[Query 14] | 181 ms | 73 ms | ✔︎ | | \[Query 15] | 1118 ms | 557 ms | | | \[Query 16] | 497 ms | 1714 ms | | | \[Query 17] | 1846 ms | 32709 ms | | | \[Query 18] | 5823 ms | 10649 ms | | | \[Query 19] | 53 ms | 206 ms | ✔︎ | | \[Query 20] | 421 ms | - | | | \[Query 21] | 1349 ms | 4434 ms | | | \[Query 22] | 258 ms | 1415 ms | |

Compile from source

General Unix

The PostgreSQL and curl development packages include `pg_config` and `curl-config` in the path, so you should be able to just run `make` (or `gmake`), then `make install`, then in your database `CREATE EXTENSION pg_clickhouse`.

Debian / Ubuntu / APT

See [PostgreSQL Apt] for details on pulling from the PostgreSQL Apt repository. ```sh theme={null} sudo apt install \ postgresql-server-19 \ libcurl4-openssl-dev \ uuid-dev \ libssl-dev \ make \ cmake \ g++ ```

RedHat / CentOS / Yum

```sh theme={null} sudo yum install \ postgresql-server \ libcurl-devel \ libuuid-devel \ openssl-libs \ automake \ cmake \ gcc ``` See [PostgreSQL Yum] for details on pulling from the PostgreSQL Yum repository.

Install from PGXN

With the above dependencies satisfied use the [PGXN client] (available as [Homebrew], [Apt] and Yum packages named `pgxnclient`) to download, compile, and install `pg_clickhouse`: ```sh theme={null} pgxn install pg_clickhouse ```

Compile and Install

To build and install the ClickHouse library and `pg_clickhouse`, run: ```sh theme={null} make sudo make install ``` If your host has several PostgreSQL installations, you might need to specify the appropriate version of `pg_config`: ```sh theme={null} export PG_CONFIG=/usr/lib/postgresql/18/bin/pg_config make sudo make install ``` If `curl-config` isn't in the path on you host, you can specify the path explicitly: ```sh theme={null} export CURL_CONFIG=/opt/homebrew/opt/curl/bin/curl-config make sudo make install ``` If you encounter an error such as: ```text theme={null} "Makefile", line 8: Need an operator ``` You need to use GNU make, which may well be installed on your system as `gmake`: ```sh theme={null} gmake gmake install gmake installcheck ``` If you encounter an error such as: ```text theme={null} make: pg_config: Command not found ``` Be sure that you have `pg_config` installed and in your path. If you used a package management system such as RPM to install PostgreSQL, be sure that the `-devel` package is also installed. If necessary tell the build process where to find it: ```sh theme={null} export PG_CONFIG=/path/to/pg_config make sudo make install ``` To install the extension in a custom prefix on PostgreSQL 18 or later, pass the `prefix` argument to `install` (but no other `make` targets): ```sh theme={null} sudo make install prefix=/usr/local/extras ``` Then ensure that the prefix is included in the following [`postgresql.conf` parameters]: ```ini theme={null} extension_control_path = '/usr/local/extras/postgresql/share:$system' dynamic_library_path = '/usr/local/extras/postgresql/lib:$libdir' ```

Testing

To run the test suite, once the extension has been installed, run ```sh theme={null} make installcheck ``` If you encounter an error such as: ```text theme={null} ERROR: must be owner of database regression ``` You need to run the test suite using a super user, such as the default "postgres" super user: ```sh theme={null} make installcheck PGUSER=postgres ```

Loading

Once `pg_clickhouse` is installed, you can add it to a database by connecting as a super user and running: ```sql theme={null} CREATE EXTENSION pg_clickhouse; ``` If you want to install `pg_clickhouse` and all of its supporting objects into a specific schema, use the `SCHEMA` clause to specify the schema, like so: ```sql theme={null} CREATE SCHEMA env; CREATE EXTENSION pg_clickhouse SCHEMA env; ```

Dependencies

The `pg_clickhouse` extension requires [PostgreSQL] 13 or higher, [libcurl], [libuuid]. Building the extension requires a C and C++ compiler, [libSSL], [GNU make], and [CMake].

Road Map

Our top focus is finishing pushdown coverage for analytic workloads before adding DML features. Our road map: * Get the remaining 10 un-pushed-down TPC-H queries optimally planned * Test and fix pushdown for the ClickBench queries * Support transparent pushdown of all PostgreSQL aggregate functions * Support transparent pushdown of all PostgreSQL functions * Allow server-level and session-level ClickHouse settings via CREATE SERVER and GUCs * Support all ClickHouse data types * Support lightweight DELETEs and UPDATEs * Support batch insertion via COPY * Add a function to execute an arbitrary ClickHouse query and return its results as a tables * Add support for pushdown of UNION queries when they all query the remote database

Authors

* [David E. Wheeler](https://justatheory.com/) * [Ildus Kurbangaliev](https://github.com/ildus) * [Ibrar Ahmed](https://github.com/ibrarahmad) * Copyright (c) 2025-2026, ClickHouse * Portions Copyright (c) 2023-2025, Ildus Kurbangaliev * Portions Copyright (c) 2019-2023, Adjust GmbH * Portions Copyright (c) 2012-2019, PostgreSQL Global Development Group [pg_clickhouse]: https://github.com/clickHouse/pg_clickhouse "pg_clickhouse on GitHub" [import foreign tables]: /products/managed-postgres/extensions/pg_clickhouse/reference#import-foreign-schema [Docker image]: https://github.com/ClickHouse/pg_clickhouse/pkgs/container/pg_clickhouse "Latest Docker release" [tutorial]: /products/managed-postgres/extensions/pg_clickhouse/tutorial "pg_clickhouse Tutorial" [PostgreSQL Apt]: https://wiki.postgresql.org/wiki/Apt [PostgreSQL Yum]: https://yum.postgresql.org [PGXN client]: https://pgxn.github.io/pgxnclient/ "PGXN Client’s documentation" [Homebrew]: https://formulae.brew.sh/formula/pgxnclient#default "PGXN client on Homebrew" [Apt]: https://tracker.debian.org/pkg/pgxnclient "PGXN client on Debian Apt" [`postgresql.conf` parameters]: https://www.postgresql.org/docs/devel/runtime-config-client.html#RUNTIME-CONFIG-CLIENT-OTHER [PostgreSQL]: https://www.postgresql.org "PostgreSQL: The World's Most Advanced Open Source Relational Database" [libcurl]: https://curl.se/libcurl/ "libcurl — your network transfer library" [libuuid]: https://linux.die.net/man/3/libuuid "libuuid - DCE compatible Universally Unique Identifier library" [GNU make]: https://www.gnu.org/software/make "GNU Make" [CMake]: https://cmake.org/ "CMake: A Powerful Software Build System" [LibSSL]: https://openssl-library.org "OpenSSL Library" [TPC-H]: https://www.tpc.org/tpch/ [re2]: https://github.com/ClickHouse/pg_re2 "pg_re2: ClickHouse-compatible regex functions using RE2" \[Query 1] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/1.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/1.sql) \[Query 2] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/2.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/2.sql) \[Query 3] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/3.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/3.sql) \[Query 4] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/4.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/4.sql) \[Query 5] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/5.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/5.sql) \[Query 6] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/6.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/6.sql) \[Query 7] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/7.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/7.sql) \[Query 8] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/8.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/8.sql) \[Query 9] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/9.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/9.sql) \[Query 10] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/10.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/10.sql) \[Query 11] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/11.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/11.sql) \[Query 12] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/12.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/12.sql) \[Query 13] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/13.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/13.sql) \[Query 14] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/14.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/14.sql) \[Query 15] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/15.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/15.sql) \[Query 16] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/16.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/16.sql) \[Query 17] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/17.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/17.sql) \[Query 18] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/18.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/18.sql) \[Query 19] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/19.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/19.sql) \[Query 20] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/20.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/20.sql) \[Query 21] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/21.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/21.sql) \[Query 22] [https://github.com/ClickHouse/pg\_clickhouse/blob/main/dev/tpch/queries/22.sql](https://github.com/ClickHouse/pg_clickhouse/blob/main/dev/tpch/queries/22.sql)