tasks/online-compute/FlinkSQL/flinksql_020/gt/ground_truth.sql

-- flinksql_020: 窗口去重 (TVF Dedup)
-- TUMBLE TVF + ROW_NUMBER 按窗口去重，保留每个窗口每个用户的第一条

-- 1. 用户事件流 datagen 源表
CREATE TABLE event_source (
    user_id INT,
    event_id BIGINT,
    event_type INT,
    event_time AS LOCALTIMESTAMP,
    WATERMARK FOR event_time AS event_time - INTERVAL '10' SECOND
) WITH (
    'connector' = 'datagen',
    'rows-per-second' = '5000',
    'fields.user_id.kind' = 'random',
    'fields.user_id.min' = '1',
    'fields.user_id.max' = '10000',
    'fields.event_id.kind' = 'random',
    'fields.event_id.min' = '1',
    'fields.event_id.max' = '1000000000',
    'fields.event_type.kind' = 'random',
    'fields.event_type.min' = '1',
    'fields.event_type.max' = '8'
);

-- 2. Console 输出表
CREATE TABLE console_output (
    window_start TIMESTAMP(3),
    window_end TIMESTAMP(3),
    user_id INT,
    event_id BIGINT,
    event_type INT
) WITH (
    'connector' = 'print'
);

-- 3. TUMBLE TVF + ROW_NUMBER 窗口去重
INSERT INTO console_output
SELECT
    window_start,
    window_end,
    user_id,
    event_id,
    event_type
FROM (
    SELECT
        window_start,
        window_end,
        user_id,
        event_id,
        event_type,
        ROW_NUMBER() OVER (
            PARTITION BY window_start, user_id
            ORDER BY event_time ASC
        ) AS rn
    FROM TABLE(
        TUMBLE(TABLE event_source, DESCRIPTOR(event_time), INTERVAL '5' MINUTE)
    )
) t
WHERE rn = 1;