Question

我需要将SQL查询转换为LINQ，但不知道如何。我有两个表：Bins和DataFromBins。 DataFromBins包含引用Bins.Id的BinId列我的查询要做的是从DataFromBins中为每个BinId选择最新行，并从Bins中为这些BinId连接一些数据。

请帮助：（

SELECT BinId, Address, Lon, Lat, MaxFillLevel, Distance
FROM (
    SELECT DataFromBins.*
    FROM (
        SELECT DataFromBins.BinId, MAX(DataFromBins.Date) AS Date
        FROM DataFromBins
        GROUP BY DataFromBins.BinId
    ) AS latest_records
        INNER JOIN DataFromBins ON DataFromBins.BinId = latest_records.BinId
            AND DataFromBins.Date = latest_records.Date
) AS most_recent
    INNER JOIN Bins ON most_recent.BinId = Bins.Id

Answer 1

我想您正在寻找下面的代码。诀窍是拆分您的子查询;）

假设[{"responseId":"6c64c1b9-5505-43b4-8fd0-a7b40367547a-fd8ff490","queryResult":{"fulfillmentMessages":[{"platform":"FACEBOOK","text":{"text":["this is response text that works! Now click on one button below"]},"message":"text"},{"platform":"FACEBOOK","card":{"buttons":[{"text":"button1","postback":"https://www.example.com/one"},{"text":"button2","postback":"https://www.example.com/two"},{"text":"button3","postback":"https://www.exaple.com/t"}],"title":"Buttons!","subtitle":"","imageUri":""},"message":"card"}, ...是您的上下文。

function callSendAPI(sender_psid, response) {
  // Construct the message body
  let request_body = {
    "recipient": {
      "id": sender_psid
    },
    "message": response
  }

  // Send the HTTP request to the Messenger Platform
  request({
    "uri": "https://graph.facebook.com/v3.2/me/messages",
    "qs": { "access_token": process.env.PAGE_ACCESS_TOKEN },
    "method": "POST",
    "json": request_body
  }, (err, res, body) => {
    if (!err) {
      console.log('message sent!')
    } else {
      console.error("Unable to send message:" + err);
    }
  });
}

SQL查询到LINQ INNER JOIN

1 个答案: