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BigQuery:标量子查询生成多个自定义维度

bigquery-standard-sql google-bigquery

user3142655 · 技术社区 · 8 年前

我试图在我的一个并集中获得一个自定义维度,但我遇到了由多个元素生成的标量子查询的问题。我相信问题就在这一准则之内。我正在尝试迁移到标准SQL,所以请用标准SQL给出答案。

SELECT
      d.value
FROM
      UNNEST(hits) AS hits,
      UNNEST(hits.customDimensions) AS d
WHERE
      d.index = 65) AS viewID,

查询的整体示例

#standardSQL
SELECT
  date,
  channelGrouping,
  viewID,
  SUM(Revenue) Revenue,
  SUM(Shipping) Shipping,
  SUM(bounces) bounces,
  SUM(transactions) transactions,
  COUNT(date) sessions
FROM (
  SELECT
    date,
    channelGrouping,
    'XXXXXXXXX' AS viewID,
    totals.totaltransactionrevenue / 1e6 Revenue,
    (
    SELECT
      SUM(hits.transaction.transactionshipping) / 1e6
    FROM
      UNNEST(hits) hits) Shipping,
    totals.bounces bounces,
    totals.transactions transactions
  FROM
    `XXXXXXXXX.ga_sessions_*`
  WHERE
    _TABLE_SUFFIX BETWEEN '20170625'
    AND '20170703'
  UNION ALL
  SELECT
    date,
    channelGrouping,
    'XXXXXXXXX' AS viewID,
    totals.totaltransactionrevenue / 1e6 Revenue,
    (
    SELECT
      SUM(hits.transaction.transactionshipping) / 1e6
    FROM
      UNNEST(hits) hits) Shipping,
    totals.bounces bounces,
    totals.transactions transactions
  FROM
    `XXXXXXXXX.ga_sessions_*`
  WHERE
    _TABLE_SUFFIX BETWEEN '20170625'
    AND '20170703'
  UNION ALL
  SELECT
    date,
    channelGrouping,
    (
    SELECT
      d.value
    FROM
      UNNEST(hits) AS hits,
      UNNEST(hits.customDimensions) AS d
    WHERE
      d.index = 65) AS viewID,
    totals.totaltransactionrevenue / 1e6 Revenue,
    (
    SELECT
      SUM(hits.transaction.transactionshipping) / 1e6
    FROM
      UNNEST(hits) hits) Shipping,
    totals.bounces bounces,
    totals.transactions transactions
  FROM
    `XXXXXXXXX.ga_sessions_*`
  WHERE
    _TABLE_SUFFIX BETWEEN '20170625'
    AND '20170703'
  UNION ALL
  SELECT
    date,
    channelGrouping,
    'XXXXXXXXX' AS viewID,
    totals.totaltransactionrevenue / 1e6 Revenue,
    (
    SELECT
      SUM(hits.transaction.transactionshipping) / 1e6
    FROM
      UNNEST(hits) hits) Shipping,
    totals.bounces bounces,
    totals.transactions transactions
  FROM
    `XXXXXXXXX.ga_sessions_*`
  WHERE
    _TABLE_SUFFIX BETWEEN '20170625'
    AND '20170703'
  UNION ALL
  SELECT
    date,
    channelGrouping,
    'XXXXXXXXX' AS viewID,
    totals.totaltransactionrevenue / 1e6 Revenue,
    (
    SELECT
      SUM(hits.transaction.transactionshipping) / 1e6
    FROM
      UNNEST(hits) hits) Shipping,
    totals.bounces bounces,
    totals.transactions transactions
  FROM
    `XXXXXXXXX.ga_sessions_*`
  WHERE
    _TABLE_SUFFIX BETWEEN '20170625'
    AND '20170703' )
GROUP BY
  date,
  channelGrouping,
  viewID

2 回复 | 直到 8 年前

Willian Fuks 8 年前

您可以在BigQuery中模拟一些数据,以更好地了解这里发生了什么。

例如,该数据模拟 hits 中的架构 ga_sessions :

WITH data AS(
  select ARRAY<STRUCT<hitNumber INT64, customDimensions ARRAY<STRUCT<index INT64, value STRING>> >> [STRUCT(1 as hitNumber, [STRUCT(1 as index, 'val1' as value), STRUCT(2 as index, 'val2' as value), STRUCT(3 as index, 'val3' as value)] as customDimensions), STRUCT(2 as hitNumber, [STRUCT(1 as index, 'val1' as value)] as customDimensions)] hits
)

select * from data

index = 1 ,您将得到相同的错误,因为在两个不同的位置,索引为1。

ARRAY 像这样:

SELECT
  array(select custd.value from unnest(hits) hits, unnest(hits.customDimensions) custd where index = 1)
FROM data

你会看到结果:

因此,在查询中,您必须适应将此值作为或者,如果对于所有值 index=65 值相同,您可以执行以下操作:

SELECT
  (select custd.value from unnest(hits) hits, unnest(hits.customDimensions) custd where index = 1 limit 1)
FROM data

这将在标量子查询中只产生一个结果。

Elliott Brossard 8 年前

问题是,一些或所有点击都有一个索引为65的自定义维度。有几种不同的方法来解决这个问题。可以使用数组子查询获取该索引的所有值:

ARRAY(
  SELECT
    d.value
  FROM
    UNNEST(hits) AS hits,
    UNNEST(hits.customDimensions) AS d
  WHERE
    d.index = 65) AS viewIDs,

这将为您提供跨点击的所有视图ID,但您还需要在联合的第一个查询中为viewID使用一个数组。另一种选择是仅从第一次点击中获取视图ID:

(
  SELECT
    d.value
  FROM
    UNNEST(hits[SAFE_OFFSET(0)].customDimensions) AS d
  WHERE
    d.index = 65) AS viewID

(
  SELECT
    d.value
  FROM
    UNNEST(hits) AS hits,
    UNNEST(hits.customDimensions) AS d
  WHERE
    d.index = 65
  LIMIT 1) AS viewID,