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