Postgres query on nested array failing to return results

February 27, 2022

I have the following query:

SELECT * FROM post p
 , jsonb_array_elements(p.meta #> '{tags, tag}') d
WHERE  d->>'tag' LIKE '%mytag%';

Which isn’t returning any results, I have an object in the post table that looks like this:

I’m not sure why this is failing, my understanding was jsonb_array_elements flattens out arrays and by selecting {tags, tag} it would get the tag string

>Solution :

The path to the nested array is meta #> '{tags}', not meta #> '{tags, tag}', so this should work

select *
from 
    post p,
    jsonb_array_elements(p.meta #> '{tags}') d
where d->>'tag' like '%mytag%';

-- or simpler

select *
from 
    post p,
    jsonb_array_elements(p.meta -> 'tags') d
where d->>'tag' like '%mytag%';