Trying to filter a SQL query on a JSON field - sql

Question

I have 4 tables in PostgreSQL:
HomeSearch(id, client_id, name)
HomeSearchNote(id, homesearch_id, text)
Client(id, user_id)
User(id)
I'm trying to query HomeSearch and return a JSON as follows but only for those entries in HomeSearch for which the Client.user_id is equal to a certain value (say, 100):
HomeSearch {
id:
name:
client: {
id:
user: {
id
}
}
notes: [{
id:
homesearch_id:
text:
},
...]
}
My SQL statement is:
SELECT
*,
( SELECT row_to_json(client) from client where homeSearch.client_id=client.id ) client,
( SELECT json_agg(row_to_json(homeSearchNote)) from homeSearchNote where homeSearchNote.homesearch_id=homeSearch.id) notes
FROM homeSearch
WHERE client->>'user_id'=100
LIMIT 5;
However, this returns:
ERROR: column "client" does not exist
LINE 19: WHERE client->>user_id=100
If I run the query without the WHERE clause in PGAdmin, I can clearly see a table with a 'client' column of type JSON.
Can anyone comment what would be the right way to place / write the WHERE clause ?
Much appreciated!

Answer 1

On way you can re-write the sql is as
With a as
(SELECT *,
( SELECT row_to_json(client) from client where homeSearch.client_id=client.id ) client,
( SELECT json_agg(row_to_json(homeSearchNote)) from homeSearchNote where homeSearchNote.homesearch_id=homeSearch.id) notes
FROM homeSearch
)
Select * from a WHERE client->>'user_id'=100
LIMIT 5;