how to suppress efficiently all empty rows in selected columns in excel vba? - excel

Question

I have found some Q/A to delete rows with empty cells in a chosen column like here. My need is a bit different, the columns are selected by the user, but this is not important.
EDIT : what is important in my use case is to delete the rows where all the cells are empty for these columns i.e. the selected columns.
The following code is working, but can only process 1,000 lines per minute on my i5. In my use case, the datasheet contains several 100k lines which means hours to process. This is not acceptable. Is there a trick to perfom it quickly please?
Sub DeleteRowsOfEmptyColumn() 'sh As Worksheet, col As String)
Application.ScreenUpdating = False
Dim sh As Excel.Worksheet: Set sh = ActiveWorkbook.ActiveSheet
Dim col As Range: Set col = Selection.EntireColumn
Dim cell
Dim area As Range: Set area = Intersect(sh.UsedRange, col)
For i = area.Rows.Count To 1 Step -1 'For Each row In area.Rows
fKeep = False
For Each cell In area.Rows(i).Cells
If Not IsEmpty(cell) Then
fKeep = True
Exit For
End If
Next cell
If Not fKeep Then
sh.Rows(i).Delete 'rowsToDelete.Add i
End If
Next i
Application.ScreenUpdating = True
End Sub
Example:
Before:
After:

Answer 1

Delete Empty Row Ranges
This is a basic example. Your feedback regarding the efficiency is appreciated.
Option Explicit
Sub DeleteRowsOfEmptyColumn()
Application.ScreenUpdating = False
Dim ws As Worksheet: Set ws = ActiveSheet ' improve
Dim crg As Range: Set crg = Selection.EntireColumn ' Columns Range
Dim srg As Range: Set srg = Intersect(ws.UsedRange, crg) ' Source Range
Dim drg As Range ' Delete Range
Dim arg As Range ' Area Range
Dim rrg As Range ' Row Range
For Each arg In srg.Areas
For Each rrg In arg.Rows
If Application.CountA(rrg) = 0 Then
If drg Is Nothing Then
Set drg = rrg
Else
Set drg = Union(drg, rrg)
End If
End If
Next rrg
Next arg
If Not drg Is Nothing Then drg.Delete
Application.ScreenUpdating = True
MsgBox "Rows deleted.", vbInformation
End Sub

Answer 2

Please, try the next way. It will process selected columns or columns having at least a selected cell. It will delete entire rows of the sheet, for the cases of all selected columns empty rows. The code only selects the rows in discussion. If they are the appropriate ones, on the last code line, Select should be replaced with Delete. It should be very fast, even for larger ranges, iterating only between blank cells range:
Sub DeleteRowsOfEmptyColumnsCells()
Dim sh As Excel.Worksheet: Set sh = ActiveSheet
Dim col As Range: Set col = Selection.EntireColumn
Dim area As Range: Set area = Intersect(sh.UsedRange, col)
Dim firstCol As Long: firstCol = area.Column: Stop
Dim areaV As Range, arr, rngDel As Range, i As Long
On Error Resume Next 'only for the case of no any empty rows existence
Set areaV = area.SpecialCells(xlCellTypeBlanks) 'a range of only empty cells
On Error GoTo 0
arr = getRows(areaV) 'extract all rows and number of columns
For i = 0 To UBound(arr(0)) 'iterate between all existing rows
If Intersect(sh.rows(arr(0)(i)), areaV).cells.count = arr(1) Then
If rngDel Is Nothing Then
Set rngDel = sh.cells(arr(0)(i), firstCol)
Else
Set rngDel = Union(rngDel, sh.cells(arr(0)(i), firstCol))
End If
End If
Next i
If Not rngDel Is Nothing Then rngDel.EntireRow.Select 'if it looks OK, Select should be replaced with Delete
End Sub
Function getRows(rng As Range) As Variant
Dim A As Range, i As Long, countC As Long
Dim arrCol, arrR, k As Long, R As Long, mtchC, mtchR
ReDim arrCol(rng.cells.count): ReDim arrR(rng.cells.count)
For Each A In rng.Areas
For i = 1 To A.Columns.count
For j = 1 To A.rows.count
mtchC = Application.match(A.cells(j, i).Column, arrCol, 0)
mtchR = Application.match(A.cells(j, i).row, arrR, 0)
If IsError(mtchC) Then
arrCol(k) = A.cells(j, i).Column: k = k + 1
End If
If IsError(mtchR) Then
arrR(R) = A.cells(j, i).row: R = R + 1
End If
Next j
Next i
Next A
ReDim Preserve arrR(R - 1)
getRows = Array(arrR, k)
End Function

Answer 3

I am working on similar kind of project. I have chosen to read the data into an array, and then work with the data in the array which improves run time significantly. Here is a copy of the function that I have used to delete / transform the data set:
Option Explicit
Option Base 1
Public Function RemoveRowFromArray(Arr As Variant, Element As String, Col As Long) As Variant
Dim i, j, c, count As Long
Dim TempArr() As Variant
For i = LBound(Arr, 1) To UBound(Arr, 1) ' looping through the columns to get desired value
If Arr(i, Col) = Element Then
count = count + 1 ' Counting the number of Elements in array / matrix
For j = i To (UBound(Arr, 1) - 1) ' Looping from the row where Element is found
For c = LBound(Arr, 2) To UBound(Arr, 2) ' Moving all elements in row 1 row up
Arr(j, c) = Arr(j + 1, c)
Next c
Next j
End If
Next i
' Populating TempArr to delete the last rows
ReDim TempArr((UBound(Arr, 1) - count), UBound(Arr, 2))
For i = LBound(TempArr, 1) To UBound(TempArr, 1)
For j = LBound(TempArr, 2) To UBound(TempArr, 2)
TempArr(i, j) = Arr(i, j)
Next j
Next i
RemoveRowFromArray = TempArr
End Function
I tested this and seems to work perfectly. A few important matters to keep in mind
Option Base 1 - This is important, when you declare an arr in VBA it starts at Index 0, when you read the arr from a data set in Excel [arr = sheet1.Range("A:D")] then the arr starting index is 1, Option Base 1 will ensure that all arr start at Index 1.
The function variables are :
Arr - the array / matrix
Element - the string that you wish to search for (in your case it would be blank)
Col - is the column number in which Element is.