Update document element by comparing to similar document

SQL++
,
1

I’m attempting to update a set of related documents. One of the documents has an array of values I was expecting in my other documents, but it was not generated properly. Instead of regenerating my entire dataset, I want to correct it. In traditional SQL I would do this with a CTE or a subselect join on the related key and set the new value. But I cannot find anything in searching this forum that makes mention to that kinda of feature. By “related” I mean that a “placeId” can have 13 languages. In english, the array is present, in every other language it is null. So I would iterate over each placeId and replace the null with the english value. Here’s an example of the pseudo SQL I would write if it was MSSQL:

update d
set d.amenities = a.amenities
from documents d join
(
select amenities, placeid from documents where language = 'english'
) a
on d.placeid = a.placeid
where d.language <> 'english'
2

Couchbase doesn’t have UPDATE joins. You can use ANSI MERGE https://blog.couchbase.com/ansi-join-enhancements-and-ansi-merge/

3

Thanks! This makes more sense :slight_smile: