How to compare column with arrays in BigQuery?

问题

I have two tables in BigQuery.

Table a keeps values in arrays. Table b has row for each value I want to have all values from table b by id if at least one value not in array from table a by the same id

WITH a as (SELECT 1 as id, ['123', 'abc', '456', 'qaz', 'uqw'] as value
UNION ALL SELECT 2, ['123', 'wer', 'thg', '10', '200']
UNION ALL SELECT 3, null),
b as (SELECT 1 as id, '123' as value
UNION ALL SELECT 1, 'abc'
UNION ALL SELECT 1, '456'
UNION ALL SELECT 1, 'qaz'
UNION ALL SELECT 1, 'uqw'
UNION ALL SELECT 2, '123'
UNION ALL SELECT 2, 'wer'
UNION ALL SELECT 2, '10'
UNION ALL SELECT 3, '200'
UNION ALL SELECT 3, 'thg'
)

What is the best way to make it?

回答1:

Below is for BigQuery Standard SQL

#standardSQL
SELECT * EXCEPT(flag)
FROM (
  SELECT b.*, COUNTIF(b.value IS NULL) OVER(PARTITION BY id) flag
  FROM `project.dataset.table_a` a, a.value 
  LEFT JOIN `project.dataset.table_b` b
  USING(id, value)
)
WHERE flag > 0
AND NOT value IS NULL

If to apply to sample data from your question - output is

Row id  value    
1   2   123  
2   2   wer  
3   2   10

In case if by your logic - id=3 should also be in output - use below

#standardSQL
SELECT * EXCEPT(flag)
FROM (
  SELECT b.*, COUNTIF(b.value IS NULL) OVER(PARTITION BY id) flag
  FROM `project.dataset.table_a` a LEFT JOIN a.value 
  FULL OUTER JOIN `project.dataset.table_b` b
  USING(id, value)
)
WHERE flag > 0
AND NOT value IS NULL

in this case output is

Row id  value    
1   2   123  
2   2   wer  
3   2   10   
4   3   200  
5   3   thg

来源：https://stackoverflow.com/questions/64011868/how-to-compare-column-with-arrays-in-bigquery

标签

google-bigquery