我目前在系统出现问题时遇到错误，提示“Column_Name不明确”＃39; ，＆＃39;连接状态=打开＆＃39;每当我按下一个与我的SQL查询完全无关的按钮时。它是唯一一个显示错误的按钮，但困扰我的是这个按钮不相关，不像其他按钮一样，点击时会激活SQL查询。我也在我的查询中使用了前缀，所以＆＃39;不明确的＆＃39;错误不应该存在。此外，我也一直保持连接状态关闭，因此连接状态=打开＆＃39;错误有点令人困惑
PS：我对计时器有疑问，但我不认为这是错误的原因，因为这个按钮仅用于编辑已经放在DataGridView上的日期，而不是数据库本身。这个唯一的按钮显示错误。
这是按钮的代码：
Private Sub Button15_Click(sender As Object, e As EventArgs) Handles Button15.Click
Dim rateprice, hourspaid, totalprice, count As Integer
BilliardHall.load_timerangeedit() 'SQL Query For Checking Available Dates Only and Fills up the Variable 'Count' if there are Results'
count = Label122.Text
x = MetroMessageBox.Show(Me, "Are you sure?", "Edit Hours Paid", MessageBoxButtons.YesNo, MessageBoxIcon.Question)
If x = vbYes Then
If TextBox4.Text = Nothing Then
MetroMessageBox.Show(Me, "Please Fill the Hours Paid Text Field", "System Information", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
ElseIf TextBox4.Text = "0" Then
MetroMessageBox.Show(Me, "Hours Paid must be Greater than 0", "System Information", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
Else
rateprice = Label108.Text
hourspaid = TextBox4.Text
totalprice = rateprice * hourspaid
If count > 0 Then
MetroMessageBox.Show(Me, "There are currently Reserved Subscriptions on the Given Schedule", "System Information", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
count = 0
ElseIf DateTimePicker3.Value <= Now.AddMinutes(-1) Then
MetroMessageBox.Show(Me, "Starting Date and Time cannot be lower than the Current Date and Time", "System Information", MessageBoxButtons.OK, MessageBoxIcon.Exclamation)
Else
SubscriptionListGrid.Item(4, SubscriptionListGrid.CurrentRow.Index).Value = TextBox4.Text
SubscriptionListGrid.Item(5, SubscriptionListGrid.CurrentRow.Index).Value = totalprice
SubscriptionListGrid.Item(6, SubscriptionListGrid.CurrentRow.Index).Value = Format(DateTimePicker3.Value, "MMMM dd, yyyy hh:mm tt")
SubscriptionListGrid.Item(7, SubscriptionListGrid.CurrentRow.Index).Value = Format(DateTimePicker3.Value.AddHours(hourspaid), "MMMM dd, yyyy hh:mm tt")
MetroMessageBox.Show(Me, "Hours Paid has been Updated", "System Information", MessageBoxButtons.OK, MessageBoxIcon.Information)
End If
End If
Else
End If
以下是＆＃39; BilliardHall.load_timerangeedit（）＆＃39;的代码。功能：
Public Function load_timerangeedit()
MysqlConn.ConnectionString = ServerString
Dim READER As MySqlDataReader
Try
MysqlConn.Open()
Dim query As String
query = "SELECT DISTINCT(ratedemand.ratedemand_id),playground.playground_id,playground.playground_name FROM bnb.ratedemand,bnb.playground WHERE ratedemand.playground_id = playground.playground_id AND ((ratedemand.ratedemand_datestart BETWEEN '" & Format(Admin_Menu.DateTimePicker3.Value, "yyyy-MM-dd HH:mm:ss tt") & "' AND '" & Format(Convert.ToDateTime(Admin_Menu.Label121.Text), "yyyy-MM-dd HH:mm:ss tt") & "' OR ratedemand.ratedemand_dateend BETWEEN '" & Format(Admin_Menu.DateTimePicker3.Value, "yyyy-MM-dd HH:mm:ss tt") & "' AND '" & Format(Convert.ToDateTime(Admin_Menu.Label121.Text), "yyyy-MM-dd HH:mm:ss tt") & "') OR (ratedemand.ratedemand_datestart < '" & Format(Admin_Menu.DateTimePicker3.Value, "yyyy-MM-dd HH:mm:ss tt") & "' AND ratedemand.ratedemand_dateend > '" & Format(Convert.ToDateTime(Admin_Menu.Label121.Text), "yyyy-MM-dd HH:mm:ss tt") & "')) AND ratedemand.playground_id = (SELECT playground.playground_id FROM bnb.playground WHERE playground.playground_name ='" & Admin_Menu.Label107.Text & "') AND ratedemand.rate_category = 'Billiard' AND (ratedemand.ratedemand_status = 'On Going' or ratedemand.ratedemand_status = 'Reserved')"
COMMAND = New MySqlCommand(query, MysqlConn)
READER = COMMAND.ExecuteReader
Dim count As Integer
count = 0
While READER.Read
count = count + 1
End While
MysqlConn.Close()
Admin_Menu.Label122.Text = count
Catch ex As Exception
MsgBox(ex.Message)
Finally
MysqlConn.Dispose()
End Try
Return True
End Function
这是我在计时器＃1中的函数代码：
Public Function load_billiardqueuetable(dgrid As DataGridView, billiardqueuecomboplayarea As ComboBox, billiardqueuecombostatus As ComboBox, billiardqueuedtp1 As DateTimePicker, billiardqueuedtp2 As DateTimePicker, rdbilliardqueuetoday As RadioButton, rdbilliardqueuefuture As RadioButton)
MysqlConn.ConnectionString = ServerString
Dim dbDataSet As New DataTable
Dim SDA As New MySqlDataAdapter
Dim bSource As New BindingSource
Try
MysqlConn.Open()
Dim query As String
If Not billiardqueuecomboplayarea.Text = "All Play Areas" And Not billiardqueuecombostatus.Text = "All" And rdbilliardqueuetoday.Checked = True Then
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd HH:mm:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd HH:mm:59") & "' ) AND ratedemand.playground_id = (SELECT playground.playground_id FROM bnb.playground WHERE playground.playground_name = '" & billiardqueuecomboplayarea.Text & "') AND ratedemand.ratedemand_status ='" & billiardqueuecombostatus.Text & "' AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
ElseIf Not billiardqueuecomboplayarea.Text = "All Play Areas" And Not billiardqueuecombostatus.Text = "All" And rdbilliardqueuefuture.Checked = True Then
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd 00:00:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd 23:59:59") & "' ) AND ratedemand.playground_id = (SELECT playground.playground_id FROM bnb.playground WHERE playground.playground_name = '" & billiardqueuecomboplayarea.Text & "') AND ratedemand.ratedemand_status ='" & billiardqueuecombostatus.Text & "' AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
ElseIf Not billiardqueuecomboplayarea.Text = "All Play Areas" And billiardqueuecombostatus.Text = "All" And rdbilliardqueuetoday.Checked = True Then
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd HH:mm:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd HH:mm:59") & "' ) AND ratedemand.playground_id = (SELECT playground.playground_id FROM bnb.playground WHERE playground.playground_name = '" & billiardqueuecomboplayarea.Text & "') AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
ElseIf Not billiardqueuecomboplayarea.Text = "All Play Areas" And billiardqueuecombostatus.Text = "All" And rdbilliardqueuefuture.Checked = True Then
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd 00:00:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd 23:59:59") & "' ) AND ratedemand.playground_id = (SELECT playground.playground_id FROM bnb.playground WHERE playground.playground_name = '" & billiardqueuecomboplayarea.Text & "') AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
ElseIf billiardqueuecomboplayarea.Text = "All Play Areas" And Not billiardqueuecombostatus.Text = "All" And rdbilliardqueuetoday.Checked = True Then
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd HH:mm:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd HH:mm:59") & "' ) AND ratedemand.ratedemand_status ='" & billiardqueuecombostatus.Text & "' AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
ElseIf billiardqueuecomboplayarea.Text = "All Play Areas" And Not billiardqueuecombostatus.Text = "All" And rdbilliardqueuefuture.Checked = True Then
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd 00:00:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd 23:59:59") & "' ) AND ratedemand.ratedemand_status ='" & billiardqueuecombostatus.Text & "' AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
ElseIf billiardqueuecomboplayarea.Text = "All Play Areas" And billiardqueuecombostatus.Text = "All" And rdbilliardqueuetoday.Checked = True Then
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd HH:mm:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd HH:mm:59") & "' ) AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
ElseIf billiardqueuecomboplayarea.Text = "All Play Areas" And billiardqueuecombostatus.Text = "All" And rdbilliardqueuefuture.Checked = True Then
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd 00:00:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd 23:59:59") & "' ) AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
Else
query = "SELECT ratedemand.sales_code as 'Confirmation Code', playground.playground_name as 'Play Area', rate.rate_name as 'Rate', ratedemand.sales_customername as 'Customer Name', ratedemand.ratedemand_hour as 'Hours Paid', DATE_FORMAT(ratedemand.ratedemand_datestart, '%M %d, %Y %h:%i %p') as 'Start', DATE_FORMAT(ratedemand.ratedemand_dateend, '%M %d, %Y %h:%i %p') as 'End', CONCAT(LPAD(TIMESTAMPDIFF(HOUR,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend), 2, 0), ':', LPAD(MOD(TIMESTAMPDIFF(MINUTE,ratedemand.ratedemand_datestart,ratedemand.ratedemand_dateend),60), 2, 0) ) as 'Time', ratedemand.ratedemand_status as 'Status' FROM bnb.ratedemand,bnb.playground,bnb.rate WHERE ratedemand.playground_id = playground.playground_id AND ratedemand.rate_id = rate.rate_id AND (ratedemand.ratedemand_date BETWEEN '" & Format(billiardqueuedtp1.Value, "yyyy-MM-dd HH:mm:00") & "' AND '" & Format(billiardqueuedtp2.Value, "yyyy-MM-dd HH:mm:59") & "' ) AND ratedemand.rate_category='Billiard' ORDER BY ratedemand.ratedemand_id DESC"
End If
COMMAND = New MySqlCommand(query, MysqlConn)
SDA.SelectCommand = COMMAND
SDA.Fill(dbDataSet)
bSource.DataSource = dbDataSet
dgrid.DataSource = bSource
SDA.Update(dbDataSet)
MysqlConn.Close()
Catch ex As Exception
MsgBox(ex.Message)
Finally
MysqlConn.Dispose()
End Try
Return True
End Function
这是我在计时器＃2中的函数的代码：
Public Function load_cancelled()
MysqlConn.ConnectionString = ServerString
Dim READER As MySqlDataReader
Try
MysqlConn.Open()
Dim query As String
query = "SELECT * FROM bnb.ratedemand WHERE ratedemand_status = 'Reserved' AND NOW() >= ADDDATE(ratedemand_datestart, INTERVAL 30 MINUTE)"
COMMAND = New MySqlCommand(query, MysqlConn)
READER = COMMAND.ExecuteReader
Dim count As Integer
count = 0
If READER.HasRows Then
While READER.Read
count = count + 1
End While
End If
MysqlConn.Close()
If count > 0 Then
MysqlConn.Open()
query = "UPDATE bnb.ratedemand SET ratedemand_status = 'Cancelled' WHERE ratedemand_status = 'Reserved' AND NOW() >= ADDDATE(ratedemand_datestart, INTERVAL 30 MINUTE)"
COMMAND = New MySqlCommand(query, MysqlConn)
READER = COMMAND.ExecuteReader
MysqlConn.Close()
Else
End If
Catch ex As Exception
MsgBox(ex.Message)
Finally
MysqlConn.Dispose()
End Try
Return True
End Function