Decimal Seperator Problem

For complete accuracy with monetary values, you should use the Decimal datatype, and you should use your front-end to control the formatting to and from European standards.

DECIMAL( length , decimals ) [UNSIGNED] [ZEROFILL]

From http://dev.mysql.com/doc/mysql/en/Choosing_types.html:

Accurate representation of monetary values is a common problem. In MySQL, you should use the DECIMAL type. This is stored as a string, so no loss of accuracy should occur. (Calculations on DECIMAL values may still be done using double-precision operations, however.) If accuracy is not too important, the DOUBLE type may also be good enough.

Thanks for the answer.. But It still accept 12.45 rather than 12,45. This is the problem that I am trying to solve. My db should accept , as decimal seperator.

MySql will not accept decimal as seperator.  I'm afraid you'll have to do the conversion on your front end.  Their is no currency type as in MSSQL, Oracle, PostgreSql or even MS Access.  Comma's are viewed as the field seperator in mysql and that's about it.

Your choices are convert on the front end to decimal, or do some programming on the MySql backend for a custom User Defined Function (search mysql udf) to convert a currency string to a decimal number.  You would have to wrap all "money" fields with a euro_to_decimal('12,45') and then use decimal_to_euro(12.45) to get it back.

As useful as it sounds, I see know of no such utility that exists right now.  Here is a list of UDF.
http://empyrean.lib.ndsu.nodak.edu/~nem/mysql/udf/

Even MySql v5 in development has no plans posted to add a money data type.


Possibly we can help with the front end issue, what are you working in?

Thanks for the answer petoskey-001. I understand your point. The important point is not to store decimal numbers with ",". Later then when I use Crytal report, that reporting program generates much more problems because of my table field type.

"Your choices are convert on the front end to decimal, or do some programming on the MySql backend for a custom User Defined Function (search mysql udf) to convert a currency string to a decimal number.  You would have to wrap all "money" fields with a euro_to_decimal('12,45') and then use decimal_to_euro(12.45) to get it back."

Can you give me some example about it?

Thanks for your help petoskey...

you can use string  for update,calculate,insert money(123,456.98 )  format and you can modify your Currency using replace and cast function.
Example :
SELECT  sum(CAST((replace(carihareket.tutar,',','.')*100) as signed)/100) FROM carihareket  where Sirano=4

1-Replace , to .
2-convert currency to signed value using CAST function
3- convert signed value  to float using *100 and  / 100
4- Sum of column
 

And  i find  second way,
1-Create your money column double(14,2)  
2-And use :  Replace(Format(sayi.ValueDouble, "###0.00"), ",", ".")   during using  insert and  update query.
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example Update::
updateCmd = "UPDATE aidatcarihareket SET tutar='" & Replace(Format(sayi.ValueDouble, "###0.00"), ",", ".") & "' WHERE SiraNo = 1" ' ,update_by='" & adminNo & "' , update_date='" + yaratilmatarihi.ToString("yyyyMMddhhmmss") + "' WHERE SiraNo = '" & SiraNo & "'"

if You use my second way you   dont need any format and string  operation when you want to use select . :)
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Example Select ::
  updateCmd = "select tutar from aidatcarihareket WHERE SiraNo = 1" ' ,update_by='" & adminNo & "' , update_date='" + yaratilmatarihi.ToString("yyyyMMddhhmmss") + "' WHERE SiraNo = '" & SiraNo & "'"

            Dim myCommand As New OdbcCommand(updateCmd, myConnection)
            myConnection.Open()
            Dim deger As Double
            deger = myCommand.ExecuteScalar()

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Erkan SALDIR 16 - January 2005