Stream Data Platform - AF analyzes the stream data input into the stream data processing engine using predefined scenarios and outputs the analysis result that meets your objectives.
A scenario is defined using the CQL query language.
The following table shows the CQL structures used by Stream Data Platform - AF.
Table 2-1 CQL structures used by Stream Data Platform - AF
No. | CQL classification | Usage | Example of applicable CQL commands |
---|---|---|---|
1 | Definition CQL | Defines streams and queries so they can be processed by the stream data processing engine. | REGISTER STREAM REGISTER QUERY, etc. |
2 | Data manipulation CQL | Defines the detailed stream data processing to be performed by a query. It is entered after the REGISTER QUERY clause. In data manipulation CQL, the following three types of operations can be defined in queries:
| SELECT FROM WHERE GROUP BY HAVING UNION, etc. |
Details about CQL are explained in 4. CQL Reference.
The following figure shows an example of using CQL to specify a query.
Figure 2-1 Example of specifying a query using CQL
Definition CQL specifies the following information to the stream data processing engine:
Data manipulation CQL defines the operations in a scenario that will analyze the data retrieved from the input stream queue.
The following figure shows the relationship between the window operations, relation operations, and stream operations defined in a query.
Figure 2-2 Relationship between operations
Each of these operations is explained below. The numbers in this explanation correspond to the numbers in the figure.