Question

Hello BigQuery社区！

我在BigQuery中有下表：Table1: Output Table BigQuery

现在我想将它转换为这种格式： Table2: Transpose Table BigQuery

您还可以查看此Google表格中的表格：https://docs.google.com/spreadsheets/d/1LF8OMql3BdBAReUX33Y2f3QMD2EW6Exw5hBOFm7EteU/edit?usp=sharing

挑战在于：实体总是不同的，每个search_term最多可包含X个实体。我真的不知道从哪里开始。如果有人可以帮助我，那会很棒。我对每一次帮助都非常满意。

非常感谢！

Answer 1

我真的不知道从哪里开始

以下可以为您提供良好的开端

#standardSQL
WITH `project.dataset.table1` AS (
  SELECT 'van rental london' search_term, 'Rental' entity, 'rental' entitydetail, 3 enittyCount UNION ALL
  SELECT 'van rental london', 'Location', 'london', 3 UNION ALL
  SELECT 'van rental london', 'Car Type', 'van', 3 UNION ALL
  SELECT 'van hire sheffield', 'Location', 'sheffield', 3 UNION ALL
  SELECT 'van hire sheffield', 'Car Type', 'van', 3 UNION ALL
  SELECT 'van hire sheffield', 'Hire', 'hire', 3 UNION ALL
  SELECT 'van hire', 'Car Type', 'van', 2 UNION ALL
  SELECT 'van hire', 'Hire', 'hire', 2 UNION ALL
  SELECT 'san diego car rental', 'Rental', 'rental', 3 UNION ALL
  SELECT 'san diego car rental', 'Location', 'San Diego', 3 UNION ALL
  SELECT 'san diego car rental', 'Vehicle Type', 'car', 3 UNION ALL
  SELECT 'long term car rental london', 'Vehicle Type', 'car', 4 UNION ALL
  SELECT 'long term car rental london', 'Location', 'london', 4 UNION ALL
  SELECT 'long term car rental london', 'Rental', 'rental', 4 UNION ALL
  SELECT 'long term car rental london', 'Long Term', 'Long Term', 4 UNION ALL
  SELECT 'london car hire', 'Location', 'london', 3 UNION ALL
  SELECT 'london car hire', 'Vehicle Type', 'car', 3 UNION ALL
  SELECT 'london car hire', 'Hire', 'hire', 3 
)
SELECT
  search_term,
  MAX(IF(pos=1, entity, NULL)) entity1, 
  MAX(IF(pos=1, entitydetail, NULL)) entitydetail1, 
  MAX(IF(pos=2, entity, NULL)) entity2, 
  MAX(IF(pos=2, entitydetail, NULL)) entitydetail2, 
  MAX(IF(pos=3, entity, NULL)) entity3, 
  MAX(IF(pos=3, entitydetail, NULL)) entitydetail3, 
  MAX(IF(pos=4, entity, NULL)) entity4, 
  MAX(IF(pos=4, entitydetail, NULL)) entitydetail4 
FROM (
  SELECT 
    search_term, entity, entitydetail, 
    ROW_NUMBER() OVER(PARTITION BY search_term ORDER BY entity) pos
  FROM `project.dataset.table1`
)
GROUP BY search_term

每个search_term最多可包含X个实体

以上查询假定您知道X的最大值，因此您需要在查询中重复两行以下X行，将N替换为相应的数字

  MAX(IF(pos=N, entity, NULL)) entityN, 
  MAX(IF(pos=N, entitydetail, NULL)) entitydetailN,

当然这可以使用脚本轻松生成（您可以使用BQ或您选择的任何语言）

您还可以查看https://stackoverflow.com/a/40766540/5221944了解更多信息

将行转换为BigQuery中的列

1 个答案: