CREATE TABLE dataset.repeated_example (
  user_id INT64,
  user_name STRING,
  tags ARRAY<STRING>,  -- 简单重复字段
  orders ARRAY<STRUCT<  -- 嵌套重复字段
    order_id STRING,
    amount FLOAT64,
    items ARRAY<STRUCT<
      item_id STRING,
      quantity INT64
    >>
  >>
);

SELECT user_id, tag
FROM dataset.repeated_example,
UNNEST(tags) AS tag;

INSERT INTO dataset.repeated_example
(user_id, user_name, tags, orders)
VALUES
(1, 'John', ['premium', 'vip'], 
 [
   STRUCT('ord123' AS order_id, 99.99 AS amount, 
     [
       STRUCT('item1' AS item_id, 2 AS quantity),
       STRUCT('item2' AS item_id, 1 AS quantity)
     ] AS items)
 ]);

UPDATE dataset.repeated_example
SET tags = ARRAY_CONCAT(tags, ['new_tag'])
WHERE user_id = 1;

SELECT user_id, ARRAY_LENGTH(tags) AS tag_count
FROM dataset.repeated_example;

-- 或者计算嵌套重复字段中的总和
SELECT 
  user_id,
  (SELECT SUM(amount) FROM UNNEST(orders)) AS total_spent
FROM dataset.repeated_example;