Creates a custom data type in the keyspace that contains one or more fields of related information, such as address (street, city, state, and postal code).

The scope of a user-defined type (UDT) is keyspace-wide.

UDTs cannot contain counter fields.

See also: DROP TYPE


CREATE TYPE [ IF NOT EXISTS ] [<keyspace_name>].<type_name>
  (<field_name> <cql_datatype> [ , <field_name> <cql_datatype> ... ]) ;
Syntax legend
Syntax conventions Description


Literal keyword.


Not literal.

< >

Variable value. Replace with a user-defined value.


Optional. Square brackets ([]) surround optional command arguments. Do not type the square brackets.

( )

Group. Parentheses ( ( ) ) identify a group to choose from. Do not type the parentheses.


Or. A vertical bar (|) separates alternative elements. Type any one of the elements. Do not type the vertical bar.


Repeatable. An ellipsis ( ... ) indicates that you can repeat the syntax element as often as required.

'<Literal string>'

Single quotation (') marks must surround literal strings in CQL statements. Use single quotation marks to preserve upper case.

{ <key> : <value> }

Map collection. Braces ({ }) enclose map collections or key value pairs. A colon separates the key and the value.


Set, list, map, or tuple. Angle brackets ( < > ) enclose data types in a set, list, map, or tuple. Separate the data types with a comma.


End CQL statement. A semicolon (;) terminates all CQL statements.


Separate the command line options from the command arguments with two hyphens ( -- ). This syntax is useful when arguments might be mistaken for command line options.

' <<schema\> ... </schema\>> '

Search CQL only: Single quotation marks (') surround an entire XML schema declaration.


Search CQL only: Identify the entity and literal value to overwrite the XML element in the schema and solrConfig files.


Parameter Description Default


Optional. Name of the keyspace that contains the table to index.

If no name is specified, the current keyspace is used.


Unique name for the type. CQL types are reserved for a list. See type names.


Define fields that are in the UDT in a comma-separated list with cql_datatype.


Valid CQL data type.

Usage notes

Once created, UDTs can be used either in a frozen or non-frozen state. In a frozen state, the UDT is stored as a single value, and cannot be altered or updated except as a whole. In a non-frozen state, the UDT is stored as a collection of fields, and can be updated individually.


Simple example

This example creates a user-defined type cycling.basic_info that consists of personal data about an individual cyclist.

CREATE TYPE IF NOT EXISTS cycling.basic_info ( 
  birthday timestamp, 
  nationality text, 
  height text,
  weight text
DESCRIBE TYPE cycling.basic_info;

After defining the UDT, you can create a table that has columns with the UDT. CQL collection columns and other columns support the use of user-defined types, as shown in Inserting UDTs.

Example with TTL

This example creates a user-defined type (UDT) cycling.basic_info_withTTL that consists of personal data about an individual cyclist, which includes the next_race column that will be set with a timestamp and time-to-live (TTL).

CREATE TYPE IF NOT EXISTS cycling.basic_info_expire (
  birthday timestamp,
  nationality text,
  height text,
  weight text,
  next_race text
DESCRIBE TYPE cycling.basic_info_expire;

To insert an entire row of data into a table using a timestamp and TTL, specify the values with an INSERT command:

INSERT INTO cycling.basic_info_TTL_expire (
  id, lastname, basics
    birthday : '1993-06-18',
    nationality : 'New Zealand',
    weight : '175',
    height : '72',
    next_race : 'Amgen Tour of California'

To insert a single UDT value with a TTL, use a UPDATE command:

UPDATE cycling.basic_info_TTL_expire USING TTL 100 
  SET basics =   {
    birthday : '1993-06-18',
    nationality : 'New Zealand',
    weight : '175',
    height : '72',
    next_race : 'Tour de France'
WHERE id = e7ae5cf3-d358-4d99-b900-85902fda9bb0;

To check the write time and TTL values of a UDT use the WRITETIME and TTL functions in a SELECT command:

SELECT WRITETIME(basics), TTL(basics) FROM cycling.basic_info_TTL_expire 
WHERE id = e7ae5cf3-d358-4d99-b900-85902fda9bb0;
 writetime(basics) | ttl(basics)
  1718927360245508 |          99

(1 rows)

 writetime(basics) | ttl(basics)
  1719804616142485 |          99

(1 rows)

It is important to note that you cannot use selection function writeTime on non-frozen UDT basics. This is because the UDT is not frozen and the write time is not stored with the UDT.

A string with a single quote in a UDT text field is returned with two quotes in queries and COPY commands. For example, if you store the string Single ' quote in a UDT text field, the string is returned as Single '' Quote.

Was this helpful?

Give Feedback

How can we improve the documentation?

© 2024 DataStax | Privacy policy | Terms of use

Apache, Apache Cassandra, Cassandra, Apache Tomcat, Tomcat, Apache Lucene, Apache Solr, Apache Hadoop, Hadoop, Apache Pulsar, Pulsar, Apache Spark, Spark, Apache TinkerPop, TinkerPop, Apache Kafka and Kafka are either registered trademarks or trademarks of the Apache Software Foundation or its subsidiaries in Canada, the United States and/or other countries. Kubernetes is the registered trademark of the Linux Foundation.

General Inquiries: +1 (650) 389-6000,