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.
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"
来源：https://stackoverflow.com/questions/42532743/cassandra-frozen-keyword-meaning