tasks/online-compute/FlinkSQL/flinksql_003_en/task.md

metadata

id: online-compute_FlinkSQL_flinksql_003
name: Word Frequency Tumbling Window 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 word frequency data stream, groups by word and opens a 1-minute tumbling window to count the occurrences of each word, and outputs the results to the console.

Business Background and Objective: Simulate a word frequency data stream using a datagen built-in table, generating 1 billion records in the word field. Use LOCALTIMESTAMP as the event time and set a 5-second watermark delay. Group by word and count the occurrences of each word over a 1-minute tumbling window, then output word and cnt to the console table.

Source Table Definition:

• word_source (word frequency stream, datagen connector):
  • word VARCHAR: Word, randomly generated (value range 1–1000 to simulate distinct words)
  • event_time: Uses LOCALTIMESTAMP to generate event time, with a WATERMARK delay of 5 seconds
  • Generation rate: rows-per-second = 1000

Output Table Definition:

• console_output (print connector):
  • word VARCHAR: Word
  • cnt BIGINT: Number of occurrences of the word within the current window

Aggregation Logic:

• Group by word, using a 1-minute tumbling window
• Aggregation metric: COUNT(*) AS cnt
• The window is defined by the TUMBLE function

Output Requirements:

• Use INSERT INTO console_output to output the results.
• Output field order: word, cnt