Using Materialized Views

Materialized Views are in synchronization with the mutating stream - they are updated by a primary key as data flows through the system. The data is updated by a given key, and it represents the latest view of the data by key.

For example: vehicleID Z latest latitude and longitude is X an Y. As the vehicle moves, the latitude and longitude are updated by vehicleID. The primary key is defined at creation time and is immutable.

Materialized Views can be created as mutating snapshots of the queried data result that is updated by a given key. The data is always the latest representation of itself by key (analogous to a primary key in most RDBMS systems)

You can query the Materialized Views using a GET request over REST, which returns a JSON response as "Content-Type: application/json". The queries are not defined at query time. Rather, they are curated, saved, and granted access through the Cloudera Platform. You can configure a REST endpoint to query the Materialized View. Multiple query conditions can be created to allow various ways to query the same data. This is sometimes referred to as a 'pull query'.

Null Keys

When a key is removed from the incoming messages from a source, SSB continues to consume them. However, it will mark the missing key as NULL at the sink. Similarly, when a key is removed from the source schema, but not from the incoming messages from the source, SSB ignores the key on the incoming stream.