VB.NET SQL显示出席每月，每年

Question

我希望将所有员工的出勤日期显示为月度报告。 所以我的数据库将是这样的。

如何以这样的方式显示它们，将计算所有月份。感谢

我尝试过使用此代码，只返回1个结果，谢谢

SELECT EMPLOYEEID ,COUNT( DISTINCT checkinDate) As April FROM ATTENDANCE WHERE checkinDate BETWEEN '4/1/2018' AND '4/30/2018'  GROUP BY EMPLOYEEID

Answer 1

安静简单。首先将员工ID存储在列表中。

 Dim employeeList as New List(of String)

 Dim con as New SqlConnection("connection string her")
 Dim cmd as New SqlCommand("Select employeeID from tableName",con)
 Dim dr as new SqlDataReader = cmd.ExecuteReader
 While dr.read
   employeeList.Add(dr(0).ToString)
 End while

'Make sure to remove duplicates from the list'

 employeeList=employeeList.Distinct.ToList()

创建一个处理employeeId，Attendence计数和月份名称的类

 Public class employees
  Public id as String
  Public month as String
  Public atCount as Integer
 End class

现在您可以使用列表中的ID并获取每个employeeId的关注度，同时确保创建我们刚刚创建的类的列表。

  Dim resultList as New List(of employees)  'We are creating the list to hold the records of each employee'

  Private sub addData()

   Dim month as Integer = 1  
   Dim year as Integer = 2014   'I created two variables which would later be used in the sql statements and furthermore.'

   Dim cmd as New SqlCommand("Select * from tablename Where employeeId=@empid,MONTH(checkinDate) = " + month + " AND YEAR(checkinDate) =" + year + "" , con)  'Here we use the MONTH(date) and YEAR function of SQL'


   cmd.Parameters.Add("@empid",sqlDbType.VarChar)
   Dim dr as SqlDataReader = cmd.ExecuteReader
   For Each id in employeeList  'Here we iterate through the list'
    cmd.Parameters(0).Value = id
    While dr.read 
     Dim emp as New employees
     emp.id = id
     emp.month = CultureInfo.CurrentCulture.DateTimeFormat.GetMonthName(month)
     emp.atCount = emp.atCount + 1  'Here we increase the count of attendence for each record that exisits'


     resultList.Add(emp)  'Finally we add the data to the list'
    End While
   dr.Close()
   If not month = 12 Then  
    month = month + 1   'Firstly we check if our "month" value exceeded 12,if it did, we count one more year , if not , we count one more month'
   Else
    year = year + 1
    month = 1
   End if        
   Next
 End sub

现在您有一个列表..您可以将它的数据保存到数据库中：

 Dim cmd as new SqlCommand("Insert Into tableName(empId,MonthName,Count)VALUES(@eid,@mname,@count)")
 cmd.Parameters.Add("@eid",sqlDbType.Varchar)
 cmd.Parameters.Add("@mname",sqlDbType.Varchar)
 cmd.Parameters.Add("@count",sqlDbType.Int)

 For Each employee in resultList  'We iterate through our final list now'


   cmd.Parameters(0).Value = employee.id
   cmd.Parameters(1).Value = employee.month
   cmd.Parameters(2).Value = employee.atCount
   cmd.ExecuteNonQuery

 Next

 'Make sure you close the connection when all is done :)'
   con.Close

或者，如果您只是想在datagridview中显示最终列表，请考虑以下代码段：

For Each employee in resultList

Dim row As DataGridViewRow = CType(dgvw1.Rows(0).Clone(), DataGridViewRow)
row.Cells(0).Value = employee.id
row.Cells(1).Value = employee.month
row.Cells(2).Value = employee.atCount
dgvw1.Rows.Add(row)

Next

希望这有助于并丰富您的知识：）