Deleting rows with values based on a column - vba

Question

I have a monthly base with almost 373,000 lines. Of these, part has a low value or is blank. I'd like to erase this lines.
I have part of this code to delete those that have zero. How to create a code that joins the empty row conditions (column D) in a more agile way.
Thanks
Sub DelRowsZero()
Dim i As Long
For i = Cells(Rows.Count, "D").End(xlUp).Row To 2 Step -1
If Cells(i, "D") = 0 Then Rows(i).Delete
Next i
End Sub

Answer 1

How about:
Sub ZeroKiller()
Dim N As Long, ToBeKilled As Range
Dim i As Long
N = Cells(Rows.Count, "A").End(xlUp).Row
For i = 1 To N
If Cells(i, "D").Value = 0 Or Cells(i, "D").Value = "" Then
If ToBeKilled Is Nothing Then
Set ToBeKilled = Cells(i, "D")
Else
Set ToBeKilled = Union(ToBeKilled, Cells(i, "D"))
End If
End If
Next i
If Not ToBeKilled Is Nothing Then
ToBeKilled.EntireRow.Delete
End If
End Sub
This assumes that A is the longest column. If this is not always the case, use:
N = Range("A1").CurrentRegion.Rows.Count

Answer 2

I am concerned about the 375K lines, who knows how long this will take to run.
Sub Button1_Click()
Dim i As Long
For i = Cells(Rows.Count, "D").End(xlUp).Row To 2 Step -1
If Cells(i, "D") = 0 Or Cells(i, "D") = "" Then
Rows(i).Delete
End If
Next i
End Sub
I'm curious to know if this works for others, it just uses the "replace" 0 values to blanks, then uses specialcells to delete the blank rows. My test of 38K rows takes 3 seconds.
Sub FindLoop()
Dim startTime As Single
startTime = Timer
'--------------------------
Columns("D:D").Replace What:="0", Replacement:="", LookAt:=xlPart, _
SearchOrder:=xlByRows, MatchCase:=True, SearchFormat:=False, _
ReplaceFormat:=False
Columns("D:D").SpecialCells(xlCellTypeBlanks).EntireRow.Delete
'---------------------------------
Debug.Print Timer - startTime
End Sub

Answer 3

There's apparently an argument to be made, that deleting rows as you find them would be faster than deleting them all at once.
So I ran the below code with 36000 rows of =RANDBETWEEN(0, 10) in columns A and B (and then copy+paste special/values), and it completed thrice in 32 seconds and dusts.
Uncommenting the currentValue assignment and replacing the array subscript accesses with currentValue comparisons adds 2.5 seconds overhead; uncommenting the IsError check adds another 3.5 seconds overhead - but then the code won't blow up if the checked cells have the slightest chance of containing some #REF! or #VALUE! error.
Every time I ran it, ~4000 rows ended up being deleted.
Note:
No implicit ActiveSheet references. The code works against Sheet2, which is the code name for Worksheets("Sheet2") - a globally scoped Worksheet object variable that you get for free for any worksheet that exists at compile-time. If the sheet you're running this against exists at compile-time, use its code name (that's the (Name) property in the Properties toolwindow / F4).
Range is hard-coded. You already know how to get the last row with data, so I didn't bother with that. You'll want to dump your working range in a variant array nonetheless.
The commented-out code can be ignored/deleted if there's no way any of the cells involved have any chance of ever containing a worksheet error value.
Public Sub SpeedyConditionalDelete()
Dim startTime As Single
startTime = Timer
'1. dump the contents into a 2D variant array
Dim contents As Variant
contents = Sheet2.Range("A1:B36000").Value2
'2. declare your to-be-deleted range
Dim target As Range
'3. iterate the array
Dim i As Long
For i = LBound(contents, 1) To UBound(contents, 1)
'4. get the interesting current value
'Dim currentValue As Variant
'currentValue = contents(i, 1)
'5. validate that the value is usable
'If Not IsError(currentValue) Then
'6. determine if that row is up for deletion
If contents(i, 1) = 0 Or contents(i, 1) = vbNullString Then
'7. append to target range
If target Is Nothing Then
Set target = Sheet2.Cells(i, 1)
Else
Set target = Union(target, Sheet2.Cells(i, 1))
End If
End If
'End If
Next
'8. delete the target
If Not target Is Nothing Then target.EntireRow.Delete
'9. output timer
Debug.Print Timer - startTime
End Sub
Of course 375K rows will run much longer than 32-38 seconds, but I can't think of a faster solution.