arrays - Postgresql将json数组选择成行和单个文本

Question

我有查询要从这样的表中获取结果:

SELECT  test_id, content::json->'scenario'
FROM    test

我得到了这些结果，场景列中有对象数组:

test_id | scenario
29      | [{"name":"OpenSignal", "task":[{"name":"speedtest"}]}, {"name":"ITest", "task":[{"name":"speedtest"}]}, {"name":"EqualOne", "task":[{"name":"flashtest"}, {"name":"web"}, {"name":"video"}]}]
30      | [{"name":"Speedtest", "task":[{"name":"speedtest"}]}, {"name":"ITest", "task":[{"name":"speedtest"}]}, {"name":"EqualOne", "task":[{"name":"flashtest"}, {"name":"web"}, {"name":"video"}]}]

对象结构是这样的:

[{
    "name": "OpenSignal",
    "task": [{
        "name": "speedtest"
    }]
}, {
    "name": "ITest",
    "task": [{
        "name": "speedtest"
    }]
}, {
    "name": "EqualOne",
    "task": [{
        "name": "flashtest"
    }, {
        "name": "web"
    }, {
        "name": "video"
    }]
}]

我怎样才能得到这样的结果:

test_id | scenario
29      | Opensignal-speedtest
29      | ITest-speedtest
29      | EqualOne-flashtest
29      | EqualOne-web
29      | EqualOne-video
30      | Opensignal-speedtest
30      | ITest-speedtest
30      | EqualOne-flashtest
30      | EqualOne-web
30      | EqualOne-video

和

test_id | scenarios
29      | OpenSignal-speedtest,ITest-speedtest,EqualOne-flashtest, EqualOne-web,EqualOne-video
30      | Speedtest-speedtest,ITest-speedtest,EqualOne-flashtest,EqualOne-web,EqualOne-video

先谢谢兄弟们

Answer 1

对于您的第一个查询，您可以这样做:

SELECT test_id, CONCAT(sub.element->'name', '-', json_array_elements(sub.element->'task')->'name') as scenario
FROM 
  (SELECT test_id, json_array_elements(content::json) as element 
   FROM test) as sub;

我使用子查询从您的原始 json 中获取元素，然后用短划线将名称与每个任务名称连接起来。

然后，为了轻松地将它们按 id 分开，我使用 string_agg 函数将其包装在另一个子查询中:

SELECT test_id, 
       string_agg(task, ',')
FROM(
    SELECT test_id, CONCAT(sub.element->'name', '-', json_array_elements(sub.element->'task')->'name') as task
    FROM 
      (SELECT test_id, json_array_elements(content::json) as element 
       FROM test) as sub
)as tasks 
 GROUP BY test_id

抱歉，如果看起来有点乱，这里有一个 sqlfiddle 链接，您可以使用。 http://sqlfiddle.com/#!17/fcb27/38