目标是删除sheet 1列A中的所有行，如果它们存在于sheet 2列A的列表中。
两列都只包含数字。
工作表1的A列可能包含重复项，如果它们不在工作表2的列表中，这也没关系。
一个选项，我不熟悉，可能会错过是自动筛选。
代码在100到1000的小数据范围内执行，但我有许多书有超过100万条记录需要清理，任何超过10,000条的记录都会使Excel没有响应并无限期冻结。

Sub remDupesfromTwoWs()

With Application 
    .EnableEvents = False 
    CalcMode = .Calculation 
    .Calculation = xlCalculationManual 
    .ScreenUpdating = False 
End With 
 
 ' set range to be searched
 
Dim masterRecordRange As Range ' declare an unallocated array.
Set masterRecordRange = Range("Sheet1!A2:A316730") ' masterRecordRange is now an allocated array
 
 ' store sheet2 column A as searchfor array
 
Dim unwantedRecords() As Variant ' declare an unallocated array.
unwantedRecords = Range("Sheet2!A1:A282393") ' unwantedRecords is now an allocated array
 
 ' foreach masterRecord loop to search masterRecordRange for match in unwantedRecords
Dim i As Double 
Dim delRange As Range 
Set delRange = Range("A" & ActiveSheet.Rows.Count) 
 
 'go through all rows starting at last row
For i = masterRecordRange.Rows.Count To 1 Step -1 
     
     ' loop through unwantedRecords check each offset
    For Each findMe In unwantedRecords 
         
         'If StrComp(cell, findMe, 1) = 0 Then not as fast
         
         ' unwantedRecord found
        If Cells(i, 1).Value = findMe Then 
             
            Set delRange = Union(delRange, Range("A" & i)) 
             
             'MsgBox i
             
            Exit For 
        End If 
    Next findMe 
Next i 
 
 'remove them all in one shot
delRange.EntireRow.Delete 
With Application 
    .EnableEvents = True 
    CalcMode = .Calculation 
    .Calculation = xlCalculationAutomatic 
    .ScreenUpdating = True 
End With 
 'possibly count and display quantity found
MsgBox "finally done!" 
 
End Sub