User-defined type (UDT) overview
A user-defined type facilitates handling multiple fields of related information in a table. Applications that required multiple tables can be simplified to use fewer tables by using a user-defined type to represent the related fields of information instead of storing the information in a separate table.
You can create, alter, and drop a user-defined type using these commands:
The address type example demonstrates how to use a user-defined type.
The cqlsh utility includes these commands for describing a user-defined type or listing all user-defined types:
Accessing a UDT in a keyspace
The scope of a user-defined type is the keyspace in which you define it.
Use dot notation to access a type from a keyspace outside its scope: keyspace name followed by a period followed the name of the type, for example: test.myType where test is the keyspace name and myType is the type name.
The database accesses the type in the specified keyspace, but does not change the current keyspace;
otherwise, if you do not specify a keyspace, the database accesses the type within the current keyspace.
