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Question

Hi i'm a novice at vb (aka learned it today) and i wrote a code that's supposed to count how many identical serial numbers are in a list (listed in a column) and post each serial number with the number of times it's listed on another sheet.
When i run my code as is, nothing happens. No errors, nothing new on the sheet. I limited my list to 1-10 in my current code because when it was 1-10000 excel crashed. Can anyone give me pointers on what's happening?? Thank you!
Public Sub count()
Dim count As Long
Dim i, j, a As Integer
Dim skuNames() As Double
a = 2
count = 0
ReDim skuNames(1)
skuNames(0) = Worksheets("RawBarcodeData").Cells(1, 1).Value
'this checks if an sku matches an existing sku in the array and adds if it does not'
For i = 1 To 10
For j = 0 To UBound(skuNames)
If Worksheets("RawBarcodeData").Cells(i, 1).Value <> skuNames(j) And j <> UBound(skuNames) Then
ElseIf Worksheets("RawBarcodeData").Cells(i, 1).Value <> skuNames(j) And j = UBound(skuNames) Then
ReDim Preserve skuNames(0 To UBound(skuNames) + 1)
skuNames(UBound(skuNames)) = Worksheets("RawBarcodeData").Cells(i, 1).Value
Else
End If
Next j
Next i
'this will count how many of each element of the array is listed and post it'
For j = 0 To UBound(skuNames)
For i = 1 To 10
If skuNames(j) = Worksheets("RawBarcodeData").Cells(i, 1).Value And i <> 10000 Then
count = count + 1
ElseIf skuNames(j) = Worksheets("RawBarcodeData").Cells(i, 1).Value And i = 10000 Then
count = count + 1
Worksheets("InventoryReport").Cells(a, 1).Value = skuNames(j)
Worksheets("InventoryReport").Cells(a, 3).Value = count
a = a + 1
count = 0
ElseIf skuNames(j) <> Worksheets("RawBarcodeData").Cells(i, 1).Value And i <> 10000 Then
ElseIf skuNames(j) <> Worksheets("RawBarcodeData").Cells(i, 1).Value And i = 10000 Then
Worksheets("InventoryReport").Cells(a, 1).Value = skuNames(j)
Worksheets("InventoryReport").Cells(a, 3).Value = count
a = a + 1
count = 0
End If
Next i
Next j
End Sub

Answer 1

maybe your code didn't crash but just entered in a long loop.
the reasons are because you didn't use
application.screenupdating= false
application.enableevents=false
application.calculation=xlManual
at the begin of the code, and then set it to true, and xlautomatic at the end.
An other reason is you ask your code too often to read again the same cell value
(Worksheets("RawBarcodeData").Cells(i, 1).Value)
Why not tell your code to memorize it at the begin of loop ?
CellI1= Worksheets("RawBarcodeData").Cells(i, 1).Value ' for example
Also when you use i and j as integer, it's slower then as Long :
dim i as long, j as long.
An other thing , in your code i is a variant, not an integer as you might think
dim i , j as integer
translates as :
dim i 'vba by default sets it as variant
dim j as integer
You can make the code simpler with asking less long "if" lines, but use more if's.
use first the if wich will occur more often (if i<>1000)
so something like:
if i<1000 then
if CellI1=Skunames(j) then
'somethinf
else 'no need to ask if <> because it's already not =
'something
end if
else 'here i=1000, no need to test if
if CellI1=Skunames(j) then
'somethinf
else 'no need to ask if <> because it's already not =
'something
end if
end if
Other thing , use variables for worksheet:
dim Sh as Worksheet
set sh=Worksheets("RawBarcodeData")
and then sh.cells(i,1).value is as better way to write it.
Later on, you can even use the "With" statement.
with sh
a= .cells(i,j).value
if skullname(j) <> .cells(i,1).value
end with
this way excel doesn't need to recalculate/reread the sheet (or variable) at each pass.
And finally, an other way to find matches of same value in a range is to use the "match" function. (i don't recommend the "find" function wich is slower)
for very big ranges of data, you can use arrays, instead of looping through cells.values :
dim MyArray() as variant 'works only with variant
dim Max as Long
dim Sh as Worksheet
set Sh=thisworkbook.sheets("Test")
with sh
max = .cells( .rows.count,1).end(xlup).row 'return the last row in first column
MyArray = .range ( .cells(1,1) , .cells ( max,1) ).value 'fast way to memorize the whole range
'can also be written = . range ( "A1:A" & max).value ' but is slower
end with
and later on, instead of working with cell(i,1).value , you have the same value in MyArray (i,1) 'and no ".value" at the end this time
Don't forget to free some memory at the end with this code:
erase MyArray
set sh=nothing
have fun with VBA

Answer 2

line of code which transfers data to other sheet ,i.e. below lines:
Worksheets("InventoryReport").Cells(a, 1).Value = skuNames(j)
Worksheets("InventoryReport").Cells(a, 3).Value = count
will only execute when "i=10000", this criteria is not met when you run code, to debug how ur program is doing, run it in debug mode, step by step (press "F8" key to execute one line at a time)