如何通过重叠 jsonb 值来连接表？ (PostgreSQL)

Question

To clarify the question, here's an example:

Table venues

id  match_ids (jsonb)
---------------------
1   []
2   [112]
3   ["25", 112]
4   [25, 112]
5   ["112"]
6   ["999"]

Table sports

id  object (jsonb)
--------------------
1   {"match_ids": [25, 112]}
2   {}
3   

To join venues and sports so that the joined table has at least one element in common, how does the SQL statement have to look like?

Here's the expected outcome:

sports.id  venue.id  venue.match_ids
-------------------------------
1          2          [112]
1          3          ["25", 112]
1          4          [25, 112]
1          5          ["112"]

I wrote the following...

select * from venues
join sports on venues.match_ids <@ sports.object::jsonb->'match_ids';

... but this resulted in

ERROR:  operator does not exist: boolean -> unknown
LINE 4:  sports.object::jsonb->'match_ids';
                             ^
HINT:  No operator matches the given name and argument types. You might need to add explicit type casts.

(Here's a fiddle: https://dbfiddle.uk/?rdbms=postgres_13&fiddle=d5263069f490828288c30b6a51a181c8 )

Any advice will be appreciated!

PS: I use PostgreSQL v13.

Answer 1

I managed to solve the issue by moving from jsonb to array and working with array intersect &&

select * from venues
join sports on ARRAY(SELECT jsonb_array_elements(match_ids)::varchar)
&&
ARRAY(SELECT jsonb_array_elements(sports.object::jsonb->'match_ids')::varchar);

https://dbfiddle.uk/?rdbms=postgres_13&fiddle=5143f236235e4411c729f41a60c69012

EDIT from the original poster

Thank you so much @Ftisiot for this brilliant solution. However, I found that this approach works if match_ids in venues has integers only. If the column has texts, it may not work. To select both texts and integers, jsonb_array_elements_text should be used.

eg

select * from venues
join sports on ARRAY(SELECT jsonb_array_elements_text(match_ids))
 &&
 ARRAY(SELECT jsonb_array_elements_text(sports.object::jsonb->'match_ids'));

https://dbfiddle.uk/?rdbms=postgres_13&fiddle=64f8fac38ccf73d38834c22e90ba4b2c

Answer 2

Change the precedence with parentheses:

... on venues.match_ids <@ (sports.object::jsonb->'match_ids')