如果我有每个员工的总分配休假列，如何计算休假余额？答案

【问题标题】：How to calculate leave balance if I have Total Allotted Leaves column for each employee?如果我有每个员工的总分配休假列，如何计算休假余额？
【发布时间】：2019-10-09 14:45:08
【问题描述】：

我有 empdetails 表，其中列作为分配的叶子。我有一个额外的专栏LeavesTaken。现在我想计算每个员工的休假余额并相应更新。

        {
            command.Connection = _connection;
            SqlDataReader reader = command.ExecuteReader();
            Employee employee = new Employee();
            List<Users.LeaveRequest> leaves = new List<Users.LeaveRequest>();
            while (reader.Read())
            {
                leaves.Add(new Users.LeaveRequest() { DayPart = reader.GetInt32(3), fromdate = reader["fromdate"].ToString(), todate = reader["todate"].ToString() });
            }
            reader.Close();
            if (leaves.Count>0)
            {
                leaveRequests = leaves;
            }
            else
            {
                leaveRequests = null;
            }

            command.CommandText = "SELECT TotalLeaves,LeavesTaken FROM empDetails WHERE empID = @empid";
            //command.Parameters.AddWithValue("@empid", CurrentUser.Employee.EmpID);
            reader = command.ExecuteReader();
            if (reader.Read())
            {
                employee.TotalLeaves = reader.GetInt32(0);
                employee.LeavesTaken = reader.GetDouble(1);
            }
            reader.Close();
            return employee;
        }````

【问题讨论】：

能否请您发布示例数据库
LeaveBalance = TotalLeaves - LeavesTaken .
为什么要在表格中更新它？您有一个 AllotedLeaves 列和一个 LeavesTaken 列，因此您可以随时计算余额以显示在应用程序中。请展示一些示例数据并明确说明您需要什么。

标签： c# asp.net

【解决方案1】：

我可以想到三个解决方案，因为您没有准确指定您想要什么，也没有示例数据：

您想要为员工合计价值：

SELECT SUM(TotalLeaves), SUM(LeavesTaken)
FROM empDetails 
WHERE empID = @empid

您希望在两个值之间取得平衡

SELECT SUM(TotalLeaves) - SUM(LeavesTaken)
FROM empDetails 
WHERE empID = @empid

如果您有每个empID 的一条记录，您也可以尝试：

SELECT TotalLeaves - LeavesTaken
FROM empDetails 
WHERE empID = @empid

【讨论】：

【解决方案2】：

我很好奇为什么你的总叶数是整数，但无论如何你可以在CommandText 中完成计算

假设AllottedLeaves, TotalLeaves, LeavesTaken这三列的数据类型为DECIMAL(4,2)

现在我想计算每个员工的休假余额并相应更新。

更新TABLE empDetails中的所有员工

{
    command.CommandText = "UPDATE empDetails " + 
                          "SET TotalLeaves = TotalLeaves - llottedLeaves, " +
                          "LeavesTaken = LeavesTaken + AllottedLeaves, " +
                          "AllottedLeaves = 0" +
                          "WHERE AllottedLeaves <> 0 AND AllottedLeaves <= TotalLeaves";
    command.Connection = _connection;
    command.ExecuteNonQuery();
}

更新TABLE empDetails中的一个员工

{
    command.CommandText = "UPDATE empDetails " + 
                          "SET TotalLeaves = TotalLeaves - llottedLeaves, " +
                          "LeavesTaken = LeavesTaken + AllottedLeaves, " +
                          "AllottedLeaves = 0" +
                          "WHERE empID = @empid";
    command.Parameters.AddWithValue("@empid", CurrentUser.Employee.EmpID);
    command.Connection = _connection;
    command.ExecuteNonQuery();
}

【讨论】：