Postgres 14

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-- with JSON *array*
SELECT jsonb_path_query(
'[
    {
        "100": {
            "name": "test",
            "priority": 5
        }
    },
    {
        "101": {
            "name": "test2",
            "priority": 10
        }
    },
    {
        "102": {
            "name": "test3",
            "priority": 15
        }
    }
]'
, '$[*] ? (@.*.priority > 10)')


jsonb_path_query


{"102": {"name": "test3", "priority": 15}}



SELECT 1


-- with JSON *array*
SELECT jsonb_path_query(
'[
    {
        "100": {
            "name": "test",
            "priority": 5
        }
    },
    {
        "101": {
            "name": "test2",
            "priority": 10
        }
    },
    {
        "102": {
            "name": "test3",
            "priority": 15
        }
    }
]'
, '$.* ? (@.priority > 10)');


jsonb_path_query


{"name": "test3", "priority": 15}



SELECT 1


-- with your original JSON *object*
SELECT jsonb_path_query(
'{
  "100": {
    "name": "test",
    "priority": 5
  },
  "101": {
    "name": "test2",
    "priority": 10
  },
  "102": {
    "name": "test3",
    "priority": 15
  }                     
}'
, '$.keyvalue() ? (@.value.priority > 10)');


jsonb_path_query


{"id": 0, "key": "102", "value": {"name": "test3", "priority": 15}}



SELECT 1


-- with your original JSON *object*, desired result
SELECT jsonb_build_object(j->>'key', j->'value')
FROM  (
   SELECT jsonb_path_query(
   '{
     "100": {
       "name": "test",
       "priority": 5
     },
     "101": {
       "name": "test2",
       "priority": 10
     },
     "102": {
       "name": "test3",
       "priority": 15
     }                     
   }'
   , '$.keyvalue() ? (@.value.priority > 10)') 
   ) sub(j);


jsonb_build_object


{"102": {"name": "test3", "priority": 15}}



SELECT 1