postgresql - Rails Postgres querying array of hash column -


i have table field of type 'json', using store array of hashes.

this schema looks like:

create_table "recommendations", force: true |t|     t.text     "message"     t.json     "vendors",               default: {}     t.datetime "created_at"     t.datetime "updated_at" end

this sample data:

>> recommendation.last.vendors [{"name" => "alphabeta"}, {"name" => "gamma"}]

how recommendations includes or has vendor named "gamma"?

i tried this

>> recommendation.where("vendors ->> 'name' = 'gamma'").count

but doesn't work.

update: found way answers here query element of array in json column

here is:

s = "select * recommendations t, json_array_elements(t.vendors) elem  elem->>'name' = 'gamma';" activerecord::base.connection.execute(s).to_a


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