Question

（使用MYSQL）我需要找出特定月份每天有多少人订阅。到目前为止，这是我的查询：

function populateData(data) {
        $(".studentPanel").show();
        for (var i = 0; i < data.length; i++) {

            $(".totalFee" + i).val(data[i].total.amount);

            for (var j = 0; j < data[i].submissions.length; j++) {

                var ts = new Date(data[i].submissions[j].created_at);
                var dateString = ts.getDate() + "-" + ts.getMonth() + "-" + ts.getYear();
                console.log(data[i].submissions[j].amount);

                var
                        tr = $("<tr>"),
                        td1 = $("<td>"),
                        td2 = $("<td>"),
                        td3 = $("<td>"),
                        td4 = $("<td>"),
                        btnUpdate = $("<button class='btn btn-primary Update'>"),
                        btnDelete = $("<button class='btn btn-danger Delete'>");

                $(".feeTable" + i).append(tr);
                tr.append(td1).append(td2).append(td3).append(td4);

                td1.append(data[i].submissions[j].amount);
                td2.append(dateString);

                td3.append(btnUpdate);
                td4.append(btnDelete);

                btnUpdate.append("Update");
                btnDelete.append("Delete");

                btnUpdate.click((event) => {
                    //put whatever your updateFees function does in here
                    console.log(event);
                    console.log(data[i].submissions[j].id); //your data is acessible
                });

                btnDelete.click((event) => {
                    //put whatever your deleteFees function does in here
                    console.log(event);
                    console.log(data[i].submissions[j].id); //your data is acessible
                });
            }
        }
    }

我希望输出给我：

SELECT COUNT(user_ID) AS Subs,  DATE(subscription_date) AS Day_Joined FROM Users GROUP BY DAY(Day_Joined), user_ID HAVING MONTH(Day_Joined) = 03 ORDER BY Day_Joined

到目前为止，它给了我

subs Day_Joined
- 10   2018-03-04
- 20   2018-03-05
- 30   2018-03-06

Answer 1

您应仅按Day_Joined分组

  SELECT COUNT(user_ID) AS Subs
       , DATE(subscription_date) AS Day_Joined
  FROM Users
  GROUP BY DATE(subscription_date)
  HAVING MONTH(DATE(subscription_date)) = 03
  ORDER BY

如果您也按user_id分组，则您不存在与众不同的user_id的计数。

如何计算特定月份每天的订阅数

1 个答案: