---
title: "ClickHouse@1"
description: "ClickHouse@1 — ClickHouse server over its HTTP interface, no driver needed"
url: "https://docs.justcat.it/reference/data-sources/providers/clickhouse-1/"
---
# ClickHouse@1


## Connects to

A ClickHouse server, self-hosted or ClickHouse Cloud.

## Example


**Properties**



Name
: MyClickHouseData

Provider
: ClickHouse@1

Technology
: ClickHouse

Connection string
: ```
  Host=localhost;
  Protocol=https;
  Port=8443;
  Username=default;
  Password=%MY_PASSWORD_FOR_CLICKHOUSE%;
  ```





**YAML**


```yaml
Data sources:
- Name: MyClickHouseData
  Provider: ClickHouse@1
  Technology: ClickHouse
  Connection string: >
    Host=localhost;
    Protocol=https;
    Port=8443;
    Username=default;
    Password=%MY_PASSWORD_FOR_CLICKHOUSE%;
```




## Connection string

A ClickHouse.Client connection string — `Key=Value` pairs separated by semicolons; the client talks to the server's HTTP interface. The keys you will use most:

| Key | Meaning |
|---|---|
| `Host` | Server name or address |
| `Protocol` | `http` or `https` |
| `Port` | `8123` for `http`, `8443` for `https`, unless your server says otherwise |
| `Database` | Database to connect to; `default` when omitted |
| `Username`, `Password` | Credentials |

The full list is in the <a href="https://clickhouse.com/integrations/csharp" target="_blank">ClickHouse C# client documentation</a>.

A password, or the whole string, can come from an environment variable — `%NAME%` is replaced with the value of `NAME`; see [How every provider is used](https://docs.justcat.it/reference/data-sources/providers/introduction/#how-every-provider-is-used "How every provider is used").

## Settings

None beyond `Connection string`.

## Query

One SQL statement in ClickHouse's dialect that returns a result set.

## Prerequisites

None. The driver ships with CAT. Windows; on Linux it has no extra dependencies and is expected to work, but it has not been tested there.

## Serving test and data source definitions

`ClickHouse@1` can also serve [lists](https://docs.justcat.it/reference/project-file/lists/ "Lists") of definitions: any statement that returns the columns of a [test](https://docs.justcat.it/reference/tests/properties/ "Test properties"), [data source](https://docs.justcat.it/reference/data-sources/properties/ "Data source properties") or [query](https://docs.justcat.it/reference/queries/properties/ "Query properties") definition works. Ready-made table scripts are in [Store definitions in a database](https://docs.justcat.it/how-to-guides/organize-and-run-tests/store-definitions-in-a-database/ "Store definitions in a database").

## Related

* [Technologies](https://docs.justcat.it/reference/data-sources/technologies/ "Technologies") — what CAT can test, with the provider behind each.