Hi everyone. My name is Xiangwei Wei and I'm new here. I wrote an adapter for Apache IoTDB recently which is a database for time series data management to support use of Apache Calcite.
However, when I finished it and tried to test its performance, I found the adapter's performance was not that fast. It took much time compared with the raw data query in the database backend. I thought maybe it was the problem of my adapter. So I did the same test on the Cassandra Adapter which is provided by Calcite source code. But it shew similar result. Executing a simple query using Cassandra Adapter takes about 1600ms - 1800ms on my PC. However, it costs only 5 ms to do the raw data query in the Cassandra database backend. Is this the general performance of adapters? Or I made something wrong? I did the test by writing a simple JDBC program to do query using standard sql. For Cassandra Adapter, I used the data proviced in "./cassandra/src/test/resources/twissandra.cql" and a simple sql statement provided in the CassandraAdapterTest which is "select * from \"userline\" where \"username\"='!PUBLIC!'". -- Best, Xiangwei Wei
