tasks/online-compute/FlinkSQL/flinksql_005/gt/ground_truth.sql

-- online_005: 滚动窗口 TopN 商品排行
-- 单源生成 @ 10 rows/sec, Tumble 10s + ROW_NUMBER Top3

-- 1. 订单流 datagen 源表
CREATE TABLE orders_source (
    order_id BIGINT,
    product_id INT,
    amount DOUBLE,
    event_time AS LOCALTIMESTAMP,
    WATERMARK FOR event_time AS event_time - INTERVAL '5' SECOND
) WITH (
    'connector' = 'datagen',
    'rows-per-second' = '10',
    'fields.order_id.kind' = 'random',
    'fields.order_id.min' = '1',
    'fields.order_id.max' = '1000000',
    'fields.product_id.kind' = 'random',
    'fields.product_id.min' = '1',
    'fields.product_id.max' = '1000',
    'fields.amount.kind' = 'random',
    'fields.amount.min' = '1',
    'fields.amount.max' = '10000'
);

-- 2. Console 输出表
CREATE TABLE console_output (
    window_start TIMESTAMP(3),
    product_id INT,
    sales DOUBLE,
    order_cnt BIGINT,
    rn BIGINT
) WITH (
    'connector' = 'print'
);

-- 3. Tumble 10s 窗口聚合 + ROW_NUMBER Top 3
INSERT INTO console_output
SELECT
    window_start,
    product_id,
    sales,
    order_cnt,
    rn
FROM (
    SELECT
        TUMBLE_START(event_time, INTERVAL '10' SECOND) AS window_start,
        product_id,
        SUM(amount) AS sales,
        COUNT(*) AS order_cnt,
        ROW_NUMBER() OVER (
            PARTITION BY TUMBLE_START(event_time, INTERVAL '10' SECOND)
            ORDER BY SUM(amount) DESC
        ) AS rn
    FROM orders_source
    GROUP BY TUMBLE(event_time, INTERVAL '10' SECOND), product_id
)
WHERE rn <= 3;