--- toc_priority: 38 toc_title: DICTIONARY --- # CREATE DICTIONARY {#create-dictionary-query} Creates a new [external 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 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}) ``` External 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. For more information, see [External Dictionaries](../../../sql-reference/dictionaries/external-dictionaries/external-dicts.md) section.