[SOLVED] Why do native CQL functions like MIN() and MAX() not work in Amazon Keyspaces?

Why do native CQL functions like MIN() and MAX() not work in Amazon Keyspaces?

I'm trying to retrieve the max value of a column in my aws keyspace table using python. I have it as a method in a class

        query = SimpleStatement('select min (timestamp) from '  + keyspace + '.'+ table_name) #+ ' limit 2'
        read = self.session.execute(query)
        
        return read.current_rows

That is my read function, and I call it :

access.read_latest_timestamp('gdapp_finance','policy_test').

I get the below error. Can someone assist me please.

InvalidRequest                            Traceback (most recent call last)
/tmp/ipykernel_223/2808458841.py in <module>
----> 1 access.read_latest_timestamp('gdapp_finance','policy_test')

/tmp/ipykernel_223/1193162473.py in read_latest_timestamp(self, keyspace, table_name)
     58         query = SimpleStatement('select min (timestamp) from '  + keyspace + '.'+ table_name , \
     59                                consistency_level=ConsistencyLevel.ONE) #+ ' limit 2'
---> 60         read = self.session.execute(query)
     61 
     62         return read.current_rows

~/.local/lib/python3.9/site-packages/cassandra/cluster.cpython-39-x86_64-linux-gnu.so in cassandra.cluster.Session.execute()

~/.local/lib/python3.9/site-packages/cassandra/cluster.cpython-39-x86_64-linux-gnu.so in cassandra.cluster.ResponseFuture.result()

InvalidRequest: Error from server: code=2200 [Invalid query] message="min is not yet supported." ```

Solution

AWS Keyspaces only supports a subset of native CQL functions. Functions like MIN() and MAX() are not supported.

Similarly, user-defined functions and aggregates are not supported either.

For the list of supported Cassandra functions, see Built-in functions in Amazon Keyspaces.

For the list of supported Cassandra APIs, see Supported Cassandra APIs, operations, and data types in Amazon Keyspaces. Cheers!