excel doubets: In an excel data base how we can avoide typing same data in more than one collums or rows?

Question

for example in A1 data entered is "XXXXXXXXX" if in A2 data entered is "XXXXXXXXX" it should data base has to reject the data

Answer 1

http://www.ozgrid.com/Excel/Formulas.htm#VALIDATION

Answer 2

it must be a macro
asuming you know excel vba,
from the Visual Basic editor,
double click on the database sheet, in the right hand side white panel
copy and paste the code below

Private Sub Worksheet_Change(ByVal Target As Range)
If Target.Count <> 1 Then Exit Sub
If Target = "" Then Exit Sub
With Cells.SpecialCells( xlCellTypeConstants)
Set c = .Find(Target, LookIn:=xlValues, LookAt:=xlWhole)
If Not c Is Nothing Then
Do
If c.Address <> Target.Address Then
MsgBox "value already in database"
With Target
.ClearContents
.Select
End With
Exit Sub
End If
Set c = .FindNext(c)
Loop While c.Address <> Target.Address
End If
End With
End Sub

save it and close it (red cross) and try to type "xxxx" in two different cells (whichever one you want, it doesn't matter)

for more details feel free to send me an email through Y Q/A
----------
I debugged a small problem

Answer 3

Use a Data Validation dropdown:
http://www.officearticles.com/excel/drop-down_using_data_validation_in_microsoft_excel.htm

Answer 4

do you % 2 sheets? If no longer: Insert a column for telephone numbers to Sheet A. be sure the column headers are the comparable on the two sheets, then replica all the information to the backside of the different. style by ability of company. verify information then delete duplicates.

Answer 5

u might consider keying in everything first, then sort them to check for repeated ones.

Answer 6

no