paul bica
paul bica

Reputation: 10715

Excel VBA Performance - 1 million rows - Delete rows containing a value, in less than 1 min

I am trying to find a way to filter large data and remove rows in a worksheet, in less than one minute

The goal:

.

Test Data:

Test data:

.

How the code works:

  1. It starts by turning all Excel features Off
  2. If the workbook is not empty and the text value to be removed exists in column 1

    • Copies the used range of column 1 to an array
    • Iterates over every value in array backwards
    • When it finds a match:

      • Appends the cell address to a tmp string in the format "A11,A275,A3900,..."
      • If the tmp variable length is close to 255 characters
      • Deletes rows using .Range("A11,A275,A3900,...").EntireRow.Delete Shift:=xlUp
      • Resets tmp to empty and moves on to the next set of rows
  3. At the end, it turns all Excel features back On

.

The main issue is the Delete operation, and total duration time should be under one minute. Any code-based solution is acceptable as long as it performs under 1 minute.

This narrows the scope to very few acceptable answers. The answers already provided are also very short and easy to implement. One performs the operation in about 30 seconds, so there is at least one answer that provides an acceptable solution, and other may find it useful as well

.

My main initial function:

Sub DeleteRowsWithValuesStrings()
    Const MAX_SZ As Byte = 240

    Dim i As Long, j As Long, t As Double, ws As Worksheet
    Dim memArr As Variant, max As Long, tmp As String

    Set ws = Worksheets(1)
    max = GetMaxCell(ws.UsedRange).Row
    FastWB True:    t = Timer

    With ws
        If max > 1 Then
            If IndexOfValInRowOrCol("Test String", , ws.UsedRange) > 0 Then
                memArr = .Range(.Cells(1, 1), .Cells(max, 1)).Value2
                For i = max To 1 Step -1

                    If memArr(i, 1) = "Test String" Then
                        tmp = tmp & "A" & i & ","
                        If Len(tmp) > MAX_SZ Then
                           .Range(Left(tmp, Len(tmp) - 1)).EntireRow.Delete Shift:=xlUp
                           tmp = vbNullString

                        End If
                    End If

                Next
                If Len(tmp) > 0 Then
                    .Range(Left(tmp, Len(tmp) - 1)).EntireRow.Delete Shift:=xlUp
                End If
                .Calculate
            End If
        End If
    End With
    FastWB False:   InputBox "Duration: ", "Duration", Timer - t
End Sub

Helper functions (turn Excel features off and on):

Public Sub FastWB(Optional ByVal opt As Boolean = True)
    With Application
        .Calculation = IIf(opt, xlCalculationManual, xlCalculationAutomatic)
        .DisplayAlerts = Not opt
        .DisplayStatusBar = Not opt
        .EnableAnimations = Not opt
        .EnableEvents = Not opt
        .ScreenUpdating = Not opt
    End With
    FastWS , opt
End Sub

Public Sub FastWS(Optional ByVal ws As Worksheet = Nothing, _
                  Optional ByVal opt As Boolean = True)
    If ws Is Nothing Then
        For Each ws In Application.ActiveWorkbook.Sheets
            EnableWS ws, opt
        Next
    Else
        EnableWS ws, opt
    End If
End Sub

Private Sub EnableWS(ByVal ws As Worksheet, ByVal opt As Boolean)
    With ws
        .DisplayPageBreaks = False
        .EnableCalculation = Not opt
        .EnableFormatConditionsCalculation = Not opt
        .EnablePivotTable = Not opt
    End With
End Sub

Finds last cell with data (thanks @ZygD - now I tested it in several scenarios):

Public Function GetMaxCell(Optional ByRef rng As Range = Nothing) As Range

    'Returns the last cell containing a value, or A1 if Worksheet is empty

    Const NONEMPTY As String = "*"
    Dim lRow As Range, lCol As Range

    If rng Is Nothing Then Set rng = Application.ActiveWorkbook.ActiveSheet.UsedRange
    If WorksheetFunction.CountA(rng) = 0 Then
        Set GetMaxCell = rng.Parent.Cells(1, 1)
    Else
        With rng
            Set lRow = .Cells.Find(What:=NONEMPTY, LookIn:=xlFormulas, _
                                        After:=.Cells(1, 1), _
                                        SearchDirection:=xlPrevious, _
                                        SearchOrder:=xlByRows)
            If Not lRow Is Nothing Then
                Set lCol = .Cells.Find(What:=NONEMPTY, LookIn:=xlFormulas, _
                                            After:=.Cells(1, 1), _
                                            SearchDirection:=xlPrevious, _
                                            SearchOrder:=xlByColumns)

                Set GetMaxCell = .Parent.Cells(lRow.Row, lCol.Column)
            End If
        End With
    End If
End Function

Returns the index of a match in the array, or 0 if a match is not found:

Public Function IndexOfValInRowOrCol( _
                                    ByVal searchVal As String, _
                                    Optional ByRef ws As Worksheet = Nothing, _
                                    Optional ByRef rng As Range = Nothing, _
                                    Optional ByRef vertical As Boolean = True, _
                                    Optional ByRef rowOrColNum As Long = 1 _
                                    ) As Long

    'Returns position in Row or Column, or 0 if no matches found

    Dim usedRng As Range, result As Variant, searchRow As Long, searchCol As Long

    result = CVErr(9999) '- generate custom error

    Set usedRng = GetUsedRng(ws, rng)
    If Not usedRng Is Nothing Then
        If rowOrColNum < 1 Then rowOrColNum = 1
        With Application
            If vertical Then
                result = .Match(searchVal, rng.Columns(rowOrColNum), 0)
            Else
                result = .Match(searchVal, rng.Rows(rowOrColNum), 0)
            End If
        End With
    End If
    If IsError(result) Then IndexOfValInRowOrCol = 0 Else IndexOfValInRowOrCol = result
End Function

.

Update:

Tested 6 solutions (3 tests each): Excel Hero's solution is the fastest so far (removes formulas)

.

Here are the results, fastest to the slowest:

.

Test 1. Total of 100,000 records, 10,000 to be deleted:

1. ExcelHero()                    - 1.5 seconds

2. DeleteRowsWithValuesNewSheet() - 2.4 seconds

3. DeleteRowsWithValuesStrings()  - 2.45 minutes
4. DeleteRowsWithValuesArray()    - 2.45 minutes
5. QuickAndEasy()                 - 3.25 minutes
6. DeleteRowsWithValuesUnion()    - Stopped after 5 minutes

.

Test 2. Total of 1 million records, 100,000 to be deleted:

1. ExcelHero()                    - 16 seconds (average)

2. DeleteRowsWithValuesNewSheet() - 33 seconds (average)

3. DeleteRowsWithValuesStrings()  - 4 hrs 38 min (16701.375 sec)
4. DeleteRowsWithValuesArray()    - 4 hrs 37 min (16626.3051757813 sec)
5. QuickAndEasy()                 - 5 hrs 40 min (20434.2104492188 sec)
6. DeleteRowsWithValuesUnion()    - N/A

.

Notes:

  1. ExcelHero method: easy to implement, reliable, extremely fast, but removes formulas
  2. NewSheet method: easy to implement, reliable, and meets the target
  3. Strings method: more effort to implement, reliable, but doesn't meet requirement
  4. Array method: similar to Strings, but ReDims an array (faster version of Union)
  5. QuickAndEasy: easy to implement (short, reliable and elegant), but doesn't meet requirement
  6. Range Union: implementation complexity similar to 2 and 3, but too slow

I also made the test data more realistic by introducing unusual values:

Upvotes: 39

Views: 43849

Answers (5)

user2693587
user2693587

Reputation:

I know I'm incredibly late with my answer here however future visitors may find it very useful.

Please Note: My approach requires an index column for the rows to end up in the original order, however if you do not mind the rows being in a different order then an index column isn't needed and the additional line of code can be removed.

My approach: My approach was to simply select all the rows in the selected range (column), sort them in ascending order using Range.Sort and then collecting the first and last index of "Test String" within the selected range (column). I then create a range from the first and last indices and use Range.EntrieRow.Delete to remove all the rows which contain "Test String".

Pros:
- It is blazing fast.
- It doesn't remove formatting, formulas, charts, pictures or anything like the method which copies to a new sheet.

Cons:
- A decent size of code to implement however it is all straight-forward.

Test Range Generation Sub:

Sub DevelopTest()
    Dim index As Long
    FastWB True
    ActiveSheet.UsedRange.Clear
    For index = 1 To 1000000 '1 million test
        ActiveSheet.Cells(index, 1).Value = index
        If (index Mod 10) = 0 Then
            ActiveSheet.Cells(index, 2).Value = "Test String"
        Else
            ActiveSheet.Cells(index, 2).Value = "Blah Blah Blah"
        End If
    Next index
    Application.StatusBar = ""
    FastWB False
End Sub

Filter And Delete Rows Sub:

Sub DeleteRowFast()
    Dim curWorksheet As Worksheet 'Current worksheet vairable

    Dim rangeSelection As Range   'Selected range
    Dim startBadVals As Long      'Start of the unwanted values
    Dim endBadVals As Long        'End of the unwanted values
    Dim strtTime As Double        'Timer variable
    Dim lastRow As Long           'Last Row variable
    Dim lastColumn As Long        'Last column variable
    Dim indexCell As Range        'Index range start
    Dim sortRange As Range        'The range which the sort is applied to
    Dim currRow As Range          'Current Row index for the for loop
    Dim cell As Range             'Current cell for use in the for loop

    On Error GoTo Err
        Set rangeSelection = Application.InputBox("Select the (N=) range to be checked", "Get Range", Type:=8)    'Get the desired range from the user
        Err.Clear

    M1 = MsgBox("This is recommended for large files (50,000 or more entries)", vbYesNo, "Enable Fast Workbook?") 'Prompt the user with an option to enable Fast Workbook, roughly 150% performace gains... Recommended for incredibly large files
    Select Case M1
        Case vbYes
            FastWB True  'Enable fast workbook
        Case vbNo
            FastWB False 'Disable fast workbook
    End Select

    strtTime = Timer     'Begin the timer

    Set curWorksheet = ActiveSheet
    lastRow = CLng(rangeSelection.SpecialCells(xlCellTypeLastCell).Row)
    lastColumn = curWorksheet.Cells(1, 16384).End(xlToLeft).Column

    Set indexCell = curWorksheet.Cells(1, 1)

    On Error Resume Next

    If rangeSelection.Rows.Count > 1 Then 'Check if there is anything to do

        lastVisRow = rangeSelection.Rows.Count

        Set sortRange = curWorksheet.Range(indexCell, curWorksheet.Cells(curWorksheet.Rows(lastRow).Row, 16384).End(xlToLeft)) 'Set the sort range

        sortRange.Sort Key1:=rangeSelection.Cells(1, 1), Order1:=xlAscending, Header:=xlNo 'Sort by values, lowest to highest

        startBadVals = rangeSelection.Find(What:="Test String", LookAt:=xlWhole, MatchCase:=False).Row
        endBadVals = rangeSelection.Find(What:="Test String", LookAt:=xlWhole, SearchDirection:=xlPrevious, MatchCase:=False).Row

        curWorksheet.Range(curWorksheet.Rows(startBadVals), curWorksheet.Rows(endBadVals)).EntireRow.Delete 'Delete uneeded rows, deleteing in continuous range blocks is quick than seperated or individual deletions.

        sortRange.Sort Key1:=indexCell, Order1:=xlAscending, Header:=xlNo 'Sort by index instead of values, lowest to highest
    End If

    Application.StatusBar = ""                    'Reset the status bar

    FastWB False                                  'Disable fast workbook

    MsgBox CStr(Round(Timer - strtTime, 2)) & "s" 'Display duration of task

Err:
    Exit Sub

End Sub

THIS CODE USES FastWB, FastWS AND EnableWS BY Paul Bica!

Times at 100K entries (10k to be removed, FastWB True):
1. 0.2 seconds.
2. 0.2 seconds.
3. 0.21 seconds.
Avg. 0.2 seconds.

Times at 1 million entries (100k to be removed, FastWB True):
1. 2.3 seconds.
2. 2.32 seconds.
3. 2.3 seconds.
Avg. 2.31 seconds.

Running on: Windows 10, iMac i3 11,2 (From 2010)

EDIT
This code was originally designed with the purpose of filtering out numeric values outside of a numeric range and has been adapted to filter out "Test String" so some of the code may be redundant.

Upvotes: 2

Excel Hero
Excel Hero

Reputation: 14764

A significant gain in speed can be achieved if the source data do not contain formulas, or if the scenario would allow (or want) the formulas to be converted into hard values during the conditional row deletions.

With the above as a caveat, my solution uses the AdvancedFilter of the range object. It's about twice as fast as DeleteRowsWithValuesNewSheet().

Public Sub ExcelHero()
    Dim t#, crit As Range, data As Range, ws As Worksheet
    Dim r&, fc As Range, lc As Range, fr1 As Range, fr2 As Range
    FastWB True
    t = Timer

        Set fc = ActiveSheet.UsedRange.Item(1)
        Set lc = GetMaxCell
        Set data = ActiveSheet.Range(fc, lc)
        Set ws = Sheets.Add
        With data
            Set fr1 = data.Worksheet.Range(fc, fc.Offset(, lc.Column))
            Set fr2 = ws.Range(ws.Cells(fc.Row, fc.Column), ws.Cells(fc.Row, lc.Column))
            With fr2
                fr1.Copy
                .PasteSpecial xlPasteColumnWidths: .PasteSpecial xlPasteAll
                .Item(1).Select
            End With
            Set crit = .Resize(2, 1).Offset(, lc.Column + 1)
            crit = [{"Column 1";"<>Test String"}]
            .AdvancedFilter xlFilterCopy, crit, fr2
            .Worksheet.Delete
        End With

    FastWB False
    r = ws.UsedRange.Rows.Count
    Debug.Print "Rows: " & r & ", Duration: " & Timer - t & " seconds"
End Sub

Upvotes: 14

paul bica
paul bica

Reputation: 10715

I'm providing the first answer as a reference

Others may find it useful, if there are no other options available

  • Fastest way to achieve the result is not to use the Delete operation
  • Out of 1 million records it removes 100,000 rows in an average of 33 seconds

.

Sub DeleteRowsWithValuesNewSheet()  '100K records   10K to delete
                                    'Test 1:        2.40234375 sec
                                    'Test 2:        2.41796875 sec
                                    'Test 3:        2.40234375 sec
                                    '1M records     100K to delete
                                    'Test 1:        32.9140625 sec
                                    'Test 2:        33.1484375 sec
                                    'Test 3:        32.90625   sec
    Dim oldWs As Worksheet, newWs As Worksheet, rowHeights() As Long
    Dim wsName As String, t As Double, oldUsedRng As Range

    FastWB True:    t = Timer

    Set oldWs = Worksheets(1)
    wsName = oldWs.Name

    Set oldUsedRng = oldWs.Range("A1", GetMaxCell(oldWs.UsedRange))

    If oldUsedRng.Rows.Count > 1 Then                           'If sheet is not empty
        Set newWs = Sheets.Add(After:=oldWs)                    'Add new sheet
        With oldUsedRng
            .AutoFilter Field:=1, Criteria1:="<>Test String"
            .Copy                                               'Copy visible data
        End With
        With newWs.Cells
            .PasteSpecial xlPasteColumnWidths
            .PasteSpecial xlPasteAll                            'Paste data on new sheet
            .Cells(1, 1).Select                                 'Deselect paste area
            .Cells(1, 1).Copy                                   'Clear Clipboard
        End With
        oldWs.Delete                                            'Delete old sheet
        newWs.Name = wsName
    End If
    FastWB False:   InputBox "Duration: ", "Duration", Timer - t
End Sub

.

At high level:

  • It creates a new worksheet, and keeps a reference to the initial sheet
  • AutoFilters column 1 on the searched text: .AutoFilter Field:=1, Criteria1:="<>Test String"
  • Copies all (visible) data from initial sheet
  • Pastes column widths, formats, and data to the new sheet
  • Deletes initial sheet
  • Renames the new sheet to the old sheet name

It uses the same helper functions posted in the question

The 99% of the duration is used by the AutoFilter

.

There are a couple limitations I found so far, the first can be addressed:

  1. If there are any hidden rows on the initial sheet, it unhides them

    • A separate function is needed to hide them back
    • Depending on implementation, it might significantly increase duration
  2. VBA related:

    • It changes the Code Name of the sheet; other VBA referring to Sheet1 will be broken (if any)
    • It deletes all VBA code associated with the initial sheet (if any)

.

A few notes about using large files like this:

  • The binary format (.xlsb) reduce file size dramatically (from 137 Mb to 43 Mb)
  • Unmanaged Conditional Formatting rules can cause exponential performance issues

    • The same for Comments, and Data validation
  • Reading file or data from network is much slower than working with a locall file

Upvotes: 16

Gary&#39;s Student
Gary&#39;s Student

Reputation: 96753

On my elderly Dell Inspiron 1564 (Win 7 Office 2007) this:

Sub QuickAndEasy()
    Dim rng As Range
    Set rng = Range("AA2:AA1000001")
    Range("AB1") = Now
    Application.ScreenUpdating = False
        With rng
            .Formula = "=If(A2=""Test String"",0/0,A2)"
            .Cells.SpecialCells(xlCellTypeFormulas, xlErrors).EntireRow.Delete
            .Clear
        End With
    Application.ScreenUpdating = True
    Range("AC1") = Now
End Sub

took about 10 seconds to run. I am assuming that column AA is available.

EDIT#1:

Please note that this code does not set Calculation to Manual. Performance will improve if the Calculation mode is set to Manual after the "helper" column is allowed to calculate.

Upvotes: 6

Andrew Toomey
Andrew Toomey

Reputation: 46

Your use of arrays in calculating the used range and row count may effect the performance. Here's another approach which in testing proves efficient across 1m+ rows of data - between 25-30 seconds. It doesn't use filters so will delete rows even if hidden. Deleting a whole row won't effect formatting or column widths of the other remaining rows.

  1. First, check if the ActiveSheet has "Test String". Since you're only interested in Column 1 I used this:

    TCount = Application.WorksheetFunction.CountIf(sht.Columns(1), "Test String")
    If TCount > 0 Then
    
  2. Instead of using your GetMaxCell() function I simply used Cells.SpecialCells(xlCellTypeLastCell).Row to get the last row:

    EndRow = sht.Cells.SpecialCells(xlCellTypeLastCell).Row
    
  3. Then loop through the rows of data:

    While r <= EndRow
    
  4. To test if the cell in Column 1 is equal to "Test String":

    If sht.Cells(r, 1).Text) = "Test String" Then
    
  5. To delete the row:

    Rows(r).Delete Shift:=xlUp
    

Putting it all together full code below. I've set ActiveSheet to a variable Sht and added turned of ScreenUpdating to improve efficiency. Since it's a lot of data I make sure to clear variables at the end.

Sub RowDeleter()
    Dim sht As Worksheet
    Dim r As Long
    Dim EndRow As Long
    Dim TCount As Long
    Dim s As Date
    Dim e As Date

    Application.ScreenUpdating = True
    r = 2       'Initialise row number
    s = Now     'Start Time
    Set sht = ActiveSheet
    EndRow = sht.Cells.SpecialCells(xlCellTypeLastCell).Row

    'Check if "Test String" is found in Column 1
    TCount = Application.WorksheetFunction.CountIf(sht.Columns(1), "Test String")
    If TCount > 0 Then

        'loop through to the End row
        While r <= EndRow
            If InStr(sht.Cells(r, 1).Text, "Test String") > 0 Then
                sht.Rows(r).Delete Shift:=xlUp
                r = r - 1
            End If
            r = r + 1
        Wend
    End If
    e = Now  'End Time
    D = (Hour(e) * 360 + Minute(e) * 60 + Second(e)) - (Hour(s) * 360 + Minute(s) * 60 + Second(s))
    Application.ScreenUpdating = True
    DurationTime = TimeSerial(0, 0, D)
    MsgBox Format(DurationTime, "hh:mm:ss")
End Sub

Upvotes: 0

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