ClickHouse/docs/en/engines/table-engines/integrations/mongodb.md
2023-07-07 10:32:44 -04:00

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---
slug: /en/engines/table-engines/integrations/mongodb
sidebar_position: 135
sidebar_label: MongoDB
---
# MongoDB
MongoDB engine is read-only table engine which allows to read data (`SELECT` queries) from remote MongoDB collection. Engine supports only non-nested data types. `INSERT` queries are not supported.
## Creating a Table {#creating-a-table}
``` sql
CREATE TABLE [IF NOT EXISTS] [db.]table_name
(
name1 [type1],
name2 [type2],
...
) ENGINE = MongoDB(host:port, database, collection, user, password [, options]);
```
**Engine Parameters**
- `host:port` — MongoDB server address.
- `database` — Remote database name.
- `collection` — Remote collection name.
- `user` — MongoDB user.
- `password` — User password.
- `options` — MongoDB connection string options (optional parameter).
:::tip
If you are using the MongoDB Atlas cloud offering please add these options:
```
'connectTimeoutMS=10000&ssl=true&authSource=admin'
```
:::
## Usage Example {#usage-example}
Create a table in ClickHouse which allows to read data from MongoDB collection:
``` sql
CREATE TABLE mongo_table
(
key UInt64,
data String
) ENGINE = MongoDB('mongo1:27017', 'test', 'simple_table', 'testuser', 'clickhouse');
```
To read from an SSL secured MongoDB server:
``` sql
CREATE TABLE mongo_table_ssl
(
key UInt64,
data String
) ENGINE = MongoDB('mongo2:27017', 'test', 'simple_table', 'testuser', 'clickhouse', 'ssl=true');
```
Query:
``` sql
SELECT COUNT() FROM mongo_table;
```
``` text
┌─count()─┐
│ 4 │
└─────────┘
```
You can also adjust connection timeout:
``` sql
CREATE TABLE mongo_table
(
key UInt64,
data String
) ENGINE = MongoDB('mongo2:27017', 'test', 'simple_table', 'testuser', 'clickhouse', 'connectTimeoutMS=100000');
```