FROZEN Datatypes

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Synopsis

FROZEN datatype is used to specify columns of binary strings that result from serializing either collections, tuples, or user-defined types.

Syntax

type_specification ::= FROZEN<type>

Where

• type is a well-formed CQL datatype (additional restrictions for type are covered in the Semantics section below).

Semantics

• Columns of type FROZEN can be part of the PRIMARY KEY.
• Type parameters of FROZEN type must be either collection types (LIST, MAP, or SET) or user-defined types.
• FROZEN types can be parameters of collection types.
• For any valid frozen type parameter type, values of type are convertible into FROZEN<type>.

Examples

You can do this as shown below.

cqlsh:example> CREATE TABLE directory(file FROZEN<LIST<TEXT>> PRIMARY KEY, value BLOB);

cqlsh:example> INSERT INTO directory(file, value) VALUES([ 'home', 'documents', 'homework.doc' ], 0x);

cqlsh:example> INSERT INTO directory(file, value) VALUES([ 'home', 'downloads', 'textbook.pdf' ], 0x12ab21ef);

cqlsh:example> UPDATE directory SET value = 0xab00ff WHERE file = [ 'home', 'documents', 'homework.doc' ];

cqlsh:example> SELECT * FROM directory;

 file                                  | value
---------------------------------------+------------
 ['home', 'downloads', 'textbook.pdf'] | 0x12ab21ef
 ['home', 'documents', 'homework.doc'] |   0xab00ff

See Also

Data Types