--- slug: /en/sql-reference/statements/create/dictionary sidebar_position: 38 sidebar_label: DICTIONARY title: "CREATE DICTIONARY" --- Creates a new [dictionary](../../../sql-reference/dictionaries/external-dictionaries/external-dicts.md) with given [structure](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-structure.md), [source](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-sources.md), [layout](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-layout.md) and [lifetime](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-lifetime.md). ## Syntax ``` sql CREATE [OR REPLACE] DICTIONARY [IF NOT EXISTS] [db.]dictionary_name [ON CLUSTER cluster] ( key1 type1 [DEFAULT|EXPRESSION expr1] [IS_OBJECT_ID], key2 type2 [DEFAULT|EXPRESSION expr2], attr1 type2 [DEFAULT|EXPRESSION expr3] [HIERARCHICAL|INJECTIVE], attr2 type2 [DEFAULT|EXPRESSION expr4] [HIERARCHICAL|INJECTIVE] ) PRIMARY KEY key1, key2 SOURCE(SOURCE_NAME([param1 value1 ... paramN valueN])) LAYOUT(LAYOUT_NAME([param_name param_value])) LIFETIME({MIN min_val MAX max_val | max_val}) SETTINGS(setting_name = setting_value, setting_name = setting_value, ...) COMMENT 'Comment' ``` The dictionary structure consists of attributes. Dictionary attributes are specified similarly to table columns. The only required attribute property is its type, all other properties may have default values. `ON CLUSTER` clause allows creating dictionary on a cluster, see [Distributed DDL](../../../sql-reference/distributed-ddl.md). Depending on dictionary [layout](../../../sql-reference/dictionaries/external-dictionaries/external-dicts-dict-layout.md) one or more attributes can be specified as dictionary keys. ## SOURCE The source for a dictionary can be a: - table in the current ClickHouse service - table in a remote ClickHouse service - file available by HTTP(S) - another database ### Create a dictionary from a table in the current ClickHouse service Input table `source_table`: ``` text ┌─id─┬─value──┐ │ 1 │ First │ │ 2 │ Second │ └────┴────────┘ ``` Creating the dictionary: ``` sql CREATE DICTIONARY id_value_dictionary ( id UInt64, value String ) PRIMARY KEY id SOURCE(CLICKHOUSE(TABLE 'source_table')) LAYOUT(FLAT()) LIFETIME(MIN 0 MAX 1000) ``` Output the dictionary: ``` sql SHOW CREATE DICTIONARY id_value_dictionary; ``` ```response CREATE DICTIONARY default.id_value_dictionary ( `id` UInt64, `value` String ) PRIMARY KEY id SOURCE(CLICKHOUSE(TABLE 'source_table')) LIFETIME(MIN 0 MAX 1000) LAYOUT(FLAT()) ``` ### Create a dictionary from a table in a remote ClickHouse service Input table (in the remote ClickHouse service) `source_table`: ``` text ┌─id─┬─value──┐ │ 1 │ First │ │ 2 │ Second │ └────┴────────┘ ``` Creating the dictionary: ``` sql CREATE DICTIONARY id_value_dictionary ( id UInt64, value String ) PRIMARY KEY id SOURCE(CLICKHOUSE(HOST 'HOSTNAME' PORT 9000 USER 'default' PASSWORD 'PASSWORD' TABLE 'source_table' DB 'default')) LAYOUT(FLAT()) LIFETIME(MIN 0 MAX 1000) ``` ### Create a dictionary from a file available by HTTP(S) ```sql CREATE DICTIONARY default.taxi_zone_dictionary ( `LocationID` UInt16 DEFAULT 0, `Borough` String, `Zone` String, `service_zone` String ) PRIMARY KEY LocationID SOURCE(HTTP(URL 'https://datasets-documentation.s3.eu-west-3.amazonaws.com/nyc-taxi/taxi_zone_lookup.csv' FORMAT 'CSVWithNames')) LIFETIME(MIN 0 MAX 0) LAYOUT(HASHED()) ``` ### Create a dictionary from another database Please see the details in [Dictionary sources](/docs/en/sql-reference/dictionaries/external-dictionaries/external-dicts-dict-sources.md/#dbms). **See Also** - For more information, see the [Dictionaries](../../../sql-reference/dictionaries/external-dictionaries/external-dicts.md) section. - [system.dictionaries](../../../operations/system-tables/dictionaries.md) — This table contains information about [Dictionaries](../../../sql-reference/dictionaries/external-dictionaries/external-dicts.md).