| --- |
| id: online-compute_FlinkSQL_flinksql_009 |
| name: Tumbling Window PV/UV Statistics |
| category: online-compute/FlinkSQL |
| timeout_seconds: 600 |
| modality: pure-text |
| engine: flink-sql |
| --- |
| ## Prompt |
| I need you to write a Flink SQL that uses a datagen built-in table to simulate a user click stream, computes PV and UV per page over a window, and writes the results to the console. |
|
|
| **Business Background and Objective**: Simulate a user click stream using a datagen built-in table (`user_id` ranging from 1–1000, `page_id` ranging from 1–50, 10,000 records per second). Compute the PV (`COUNT(*)`) and UV (`COUNT(DISTINCT user_id)`) per page over a 1-minute tumbling window. Output the results (window start, window end, `page_id`, `pv`, `uv`) to the console. |
|
|
| **Source Table Definition**: |
| - `click_source` (user click stream, datagen connector): |
| - `user_id INT`: User ID, randomly generated in the range 1–1000 |
| - `page_id INT`: Page ID, randomly generated in the range 1–50 |
| - `event_time`: Uses `LOCALTIMESTAMP` to generate event time, with a WATERMARK delay of 5 seconds |
| - Generation rate: `rows-per-second = 10000` |
|
|
| **Output Table Definition**: |
| - `console_output` (print connector): |
| - `window_start TIMESTAMP`: Window start time |
| - `window_end TIMESTAMP`: Window end time |
| - `page_id INT`: Page ID |
| - `pv BIGINT`: Page views (PV) |
| - `uv BIGINT`: Unique visitors (UV) |
|
|
| **Query Logic**: |
| - Window: `TUMBLE(event_time, INTERVAL '1' MINUTE)` tumbling window |
| - Grouping: Group by `page_id` and the window |
| - PV: `COUNT(*)` to compute page views |
| - UV: `COUNT(DISTINCT user_id)` to compute unique visitors |
| - Window functions: Use `TUMBLE_START` / `TUMBLE_END` to obtain the window start and end times |
|
|
| **Output Requirements**: |
| - Use `INSERT INTO console_output` to output the results. |
| - Output field order: `window_start`, `window_end`, `page_id`, `pv`, `uv` |
|
|
