2020-10-01 10:59:51 +00:00
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---
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toc_priority: 6
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toc_title: EmbeddedRocksdb
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---
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# EmbeddedRocksdb Engine {#EmbeddedRocksdb-engine}
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This engine allows integrating ClickHouse with [rocksdb](http://rocksdb.org/).
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`EmbeddedRocksdb` lets you:
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## Creating a Table {#table_engine-EmbeddedRocksdb-creating-a-table}
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``` sql
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CREATE TABLE [IF NOT EXISTS] [db.]table_name [ON CLUSTER cluster]
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(
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name1 [type1] [DEFAULT|MATERIALIZED|ALIAS expr1],
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name2 [type2] [DEFAULT|MATERIALIZED|ALIAS expr2],
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...
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) ENGINE = EmbeddedRocksdb PRIMARY KEY(primary_key_name)
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```
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Required parameters:
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- `primary_key_name` – any column name in the column list.
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Example:
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``` sql
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CREATE TABLE test
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(
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`key` String,
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`v1` UInt32,
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`v2` String,
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`v3` Float32,
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)
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ENGINE = EmbeddedRocksdb
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PRIMARY KEY key
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```
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## Description {#description}
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- `primary key` must be specified, only support one primary key. The primary key will serializeBinary as rocksdb key.
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- Columns other than the primary key will be serializeBinary as rocksdb value in corresponding order.
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2020-10-01 11:00:03 +00:00
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- Queries with key `equals` or `in` filtering will be optimized to multi keys look up from rocksdb.
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