Creating a user-defined type (UDT)
User-Defined Types (UDTs) can be used to attach multiple data fields to a column.
User-defined types (UDTs) can attach multiple data fields, each named and typed, to a single column. The fields used to create a UDT may be any valid data type, including collections and other existing UDTs. After a UDT is created, it can be used to define a table column.
Procedure
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Use the cycling keyspace.
USE cycling;
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Create a user-defined type named basic_info.
CREATE TYPE cycling.basic_info ( birthday timestamp, nationality text, weight text, height text );
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Create a table for storing cyclist data in columns of type
basic_info. Use the frozen keyword in the definition of the
user-defined type column.
The frozen keyword is not required for UDTs that contain only non-collection fields.
When using the frozen keyword, you cannot update parts of a user-defined type value. The entire value must be overwritten. The database treats the value of a frozen, user-defined type like a blob.
CREATE TABLE cycling.cyclist_stats ( id uuid PRIMARY KEY, lastname text, basics FROZEN<basic_info> );
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A user-defined type can be nested in another column type. The example below
nests a UDT in a frozen list named
races
.CREATE TYPE cycling.race ( race_title text, race_date timestamp, race_time text ); CREATE TABLE cycling.cyclist_races ( id UUID PRIMARY KEY, lastname text, firstname text, races list<FROZEN <race>> );