Macro runs SQL query in loop (104 times) after entering data in first cell - vba

Question

I've a macro which runs when user enters data in first cell. However, when I enter the data in first cell the macro executes the sql query and runs in the loop (104 times) and puts the column headers of the sql select statement on the spreadsheet.
Here is my macro:
Sub JobTaskHistory(ByVal Target As Range)
Dim sqlstring As String
Dim connstring As String
Dim Strcode As String
Dim rangeTest As Range
Set rangeTest = Range("A1")
'Strcode = Trim(InputBox("Please enter a Job Number", "Job Task history"))
Strcode = Target.Cells(1, 1).Value
sqlstring = "select distinct m.JobNumber , cast(m.ExpectedDate as DATE) 'Ship Date' , m.QuantityOrdered 'Quantity' & _
" from ArchiveJobHeader m left join AuxiliaryInfoFile af (nolock) on af.jobnumber=m.jobnumber left join JobExtra j on j.JobNumber = m.JobNumber " & _
" where m.JobNumber = '" & Trim(Strcode) & "'" & _
" order by 'Resulttime'"
connstring = "ODBC;DSN=Test;UID=Test;PWD=Test123"
Dim thisQT As QueryTable
Dim lastRow As Long, nextRow As Long
lastRow = Sheets("Sheet1").Range("A" & Rows.Count).End(xlUp).Row
nextRow = lastRow + 1
'Set thisQT = ActiveSheet.QueryTables.Add(Connection:=connstring, Destination:=Range("a1", "a1000"))
Set thisQT = ActiveSheet.QueryTables.Add( _
Connection:=connstring, _
Destination:=Range("A" & nextRow))
thisQT.BackgroundQuery = False
thisQT.Sql = sqlstring
thisQT.Refresh
End Sub
Private Sub Worksheet_Change(ByVal Target As Range)
Call JobTaskHistory(Target)
End Sub

Answer 1

You can solve this by placing a Public variable in the module that contains the macro. If you don't have your macro in a module, you will need to put it in one, because this won't work from the Sheet code.
What Happens:
A value changes on the sheet.
The worksheet change event calls the macro.
The macro sets the public variable to TRUE.
Things change, triggering the change event again.
The change event tests for inProgress and if it IS TRUE, skips calling the macro.
The macro completes, and sets inProgress to False again.
In your module:
Public inProgress As Boolean
Sub JobTaskHistory(ByVal Target As Range)
inProgress = True
'YOUR CODE AS WRITTEN
inProgress = False
End Sub
In the worksheet code:
Private Sub Worksheet_Change(ByVal Target As Range)
If inProgress = False Then
Call JobTaskHistory(Target)
End If
End Sub
note:
Any time you have a change event, look to see what the scope is (ie, "worksheet_change"), because when you run anything as a result of it, if it causes the event to trigger again, you will have circular looping.
If you get caught in a loop you can't exit, try using 'Ctrl+PauseBreak'