====== HW 5 – Wide-column data stores. Cassandra ======
**(5 points)**

  - Design the table schemas based on the analytical tasks (see HW1) that are intended to be solved with Cassandra.
    * The schemas must strictly follow Cassandra’s query-based modeling principles: correct selection of partition keys and clustering columns, and denormalization.
    * Materialized views are not allowed.
    * ALLOW FILTERING is forbidden. All queries must be supported by schema design.
  - Insert the data into Cassandra using the CSV/JSON generated for the project (see HW0).
    * Load only the data required for the analytical tasks. Avoid unnecessary attributes or tables.
  - Implement and run the queries (see HW1).
    * Provide efficient CQL queries that leverage the partitioning and clustering design.
    * Demonstrate how queries are optimized by schema design (no filtering scans).
    * For time-series data, show partitioning and clustering strategies for scalability.
  - Prepare a detailed report including:
    * The text from HW0 and HW1 (edited if necessary);
    * Full schema creation statements with a brief explanation of design decisions;
    * The data import commands/scripts;
    * All analytical queries:
      * Task number (as in HW1);
      * Description of the analytical question;
      * Full CQL query with a short explanation of how the schema supports it;
      * Screenshot of the query result.

**Important:**
  * If certain analytical tasks are not feasible under Cassandra’s data model, replace them with other meaningful tasks and update earlier work (HW0/HW1).
  * Use denormalization and query-driven schema design to avoid ALLOW FILTERING.

Submission:
  * Submit the **HW5.docx** file to the BRUTE system.
  * Submit the **hw5.cql** file to the NoSQL server (nosql.felk.cvut.cz), containing Cassandra CQL commands with brief explanatory comments.


**Execution:**
    * Execute the following shell command to evaluate the whole CQL script
        <code bash>cqlsh -u $username -p $password -k $KeyspaceName -f $ScriptFile</code>
      * ''$KeyspaceName'' is a name of keyspace that should be used (must already exist), e.g. ''f241_login''
      * ''$ScriptFile'' is a file with CQL queries to be executed, i.e. ''script.cql''
  * Tools:
    * [[http://cassandra.apache.org/|Apache Cassandra]] 4.1.6 (installed on the NoSQL server)
  * References:
    * [[http://cassandra.apache.org/doc/latest/cql/|The Cassandra Query Language (CQL)]]
  * Server: **nosql.felk.cvut.cz**
    Don’t forget to run the homework submission script!
  * Deadline
    Sunday 7. 12. 2025 until 23:59