Cassandra frozen keyword meaning



What's the meaning of the frozen keyword in Cassandra?I'm trying to read this documentation page: Using a user-defined type, but their explanation for the frozen keyword (which they use in their examples) is not clear enough for me: To support future capabilities, a column definition of a user-defined or tuple type requires the frozen keyword. Cassandra serializes a frozen value having multiple components into a single value. For examples and usage information, see "Using a user-defined type", "Tuple type", and Collection type.I haven't found any other definition or a clear explanation for that in the net.
 edited Sep 22 '17 at 18:01

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 asked Mar 1 '17 at 13:12

 AlonAlon
 
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 In Cassandra if you define UDT or Collection as frozen, you can't update UDT's or collection's individual item, you have to reinsert with full value. A frozen value serializes multiple components into a single value. Non-frozen types allow updates to individual fields. Cassandra treats the value of a frozen type as a blob. The entire value must be overwritten.Source : https://docs.datastax.com/en/cql/3.1/cql/cql_reference/collection_type_r.html@Alon : "Long story short: frozen = immutable"
 edited Feb 8 '18 at 19:20

 
 

 answered Mar 1 '17 at 14:13

 Ashraful IslamAshraful Islam
 
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