Final answer:
In Apache Cassandra, a 'wide row' is a row with a large number of columns, enabling efficient storage and querying of large data sets associated with a given partition key, which is in contrast to the normalization approach in traditional relational databases.
Step-by-step explanation:
In Apache Cassandra, the term wide row can be attributed to a row that contains a vast number of columns. This is a data model pattern where each row is identified by a partition key, and can store a large amount of data by having numerous column-value pairs within the same row. Cassandra's design allows for wide rows as it is optimized for write and read operations that handle a large amount of data efficiently. Unlike traditional relational databases that normalize data into multiple tables, wide rows in Apache Cassandra enable denormalization where all data related to a particular key can be stored in a single row structure.
When modeling data for Cassandra, a wide row approach allows for efficient querying, as data that is accessed together can be stored together. This reduces the need for joins, which are not performant in distributed databases like Cassandra. It's essential to design the database schema in a way that aligns with query patterns to leverage the benefits of wide rows fully. An example of a wide row could be storing user activity logs where each partition key is a user ID, and column-value pairs represent individual activities with their timestamps.