Question

我正在尝试创建一个视图，该视图返回带有文档价格变化的名称。

"name": "USD"
"price_changes": {
    "0min": 0,
    "15min": 0,
    "30min": 0,
    "60min": 0,
    "90min": 0,
    "120min": 0,
    "150min": 0,
    "180min": 0,
    "210min": 0,
    "240min": 0,
    "270min": 0,
    ...

我想要的是一个返回“price_changes”中所有数据的视图。

{"id":"c95718ebd00b13bc9a8b03a0e5005d51",
"key": {"0min":0,"15min":0,"30min":0,"60min":0,"90min":0,"120min":0,"150min":0,...}
{"id":"c95718ebd00b13bc9a8b03a0e5006906",
"key": {"0min":0,"15min":0,"30min":0,"60min":0,"90min":0,"120min":0,"150min":0,...}
...

返回一组行的视图，例如每个名称只有“0mins”，“15mins”和“30mins”。

像：

"id":"c95718ebd00b13bc9a8b03a0e5005d51",
"name": "USD", 
"key": {"0min":0,"15min":0,"30min":0}

单独地

"id":"c95718ebd00b13bc9a8b03a0e5006906",
"name": "GBP", 
"key": {"0min":0,"15min":0,"30min":0}

到目前为止我所拥有的是（但不会返回我想要的内容）：

function (doc) {
var mins, value;
if (doc.price_changes) {
  for (mins in doc.price_changes) {
    value = doc.price_changes[mins];
    emit(doc.id, [value], mins);
    }
  }
}

任何想法的人？我真的找不到像这样返回数据的任何内容。

Answer 1

首先，在您的视图地图功能中，您发出三件事：

emit(doc.id, [value], mins);

这不应该是什么。 As documented，你需要发出键/值对（当然，键或值可以是很多东西的数组）：

Map函数接受单个文档作为参数和（可选）发出存储在视图中的（）键/值对。

根据你的说法：

我想要的是一个视图，它返回＆＃34; price_changes＆＃34;中的所有数据。

我的理解是你需要以下地图功能：

function (doc) {
  var mins, value;
  if (doc.price_changes) {
    for (mins in doc.price_changes) {
      value = doc.price_changes[mins];
      emit(mins, [value, doc._id]);
    }
  }
}

它返回：

$ curl -k -X GET https://admin:****@192.168.1.106:6984/sample-repl/_design/price/_view/price
{"total_rows":11,"offset":0,"rows":[
{"id":"so_q","key":"0min","value":[0,"so_q"]},
{"id":"so_q","key":"120min","value":[0,"so_q"]},
{"id":"so_q","key":"150min","value":[0,"so_q"]},
{"id":"so_q","key":"15min","value":[0,"so_q"]},
{"id":"so_q","key":"180min","value":[0,"so_q"]},
{"id":"so_q","key":"210min","value":[0,"so_q"]},
{"id":"so_q","key":"240min","value":[0,"so_q"]},
{"id":"so_q","key":"270min","value":[0,"so_q"]},
{"id":"so_q","key":"30min","value":[0,"so_q"]},
{"id":"so_q","key":"60min","value":[0,"so_q"]},
{"id":"so_q","key":"90min","value":[0,"so_q"]}
]}

我不确定上述结果是否符合您的要求，如果我错了，请告诉我。

谢谢！只是想知道我将如何返回说前三个（如：0分钟， 15分钟，30分钟）

要获得前3个，您可以使用limit这样的查询参数，如您所见，它将返回前3个：

$ curl -k -X GET https://admin:****@192.168.1.106:6984/sample-repl/_design/price/_view/price?limit=3
{"total_rows":11,"offset":0,"rows":[
{"id":"so_q","key":"0min","value":[0,"so_q"]},
{"id":"so_q","key":"120min","value":[0,"so_q"]},
{"id":"so_q","key":"150min","value":[0,"so_q"]}
]}

一般情况下，您可以使用query parameters来获取您想要的视图/索引。

Couchdb视图返回行

1 个答案: