How to store tax (vat) value in SQL

Hi everyone.

Could someone tell me , how to store vat value into SQL and during the calculation? For now i am storing into sql like dcimal (4,2). Everthing is ok during the call up process . I retrieve data from sql into datagridview and there data are displayed like i store into db. But the vat value is stored in this format 1.18 for 18.00 % for calculation purpose. But i want into the vat column into the datagridview to be a kind of a mask for vat filed (data to be displayed 18.00 not 1.18)

Here is the declared data columns

//Made a new DataColumn to populate above DataTable
dc.DataType = System.Type.GetType("System.Int32");//Defined the DataType inside, this can be [[int]] if you want.
dc.ColumnName = "Barcode";//Gave it a name (important for the custom expression - can only be one word so use underscores if you need multiple words)
dc.ReadOnly = true;

DataColumn dc2 = new DataColumn();
dc2.DataType = System.Type.GetType("System.String");
dc2.ColumnName = "NAME";
dc2.ReadOnly = true;

DataColumn dc4 = new DataColumn();
dc4.DataType = System.Type.GetType("System.Decimal");
dc4.ColumnName = "PRICE";
dc4.ReadOnly = false;

DataColumn dc3 = new DataColumn();
dc3.DataType = System.Type.GetType("System.Decimal");
dc3.ColumnName = "QTY";

DataColumn dc5 = new DataColumn();
dc5.DataType = System.Type.GetType("System.Decimal");
dc5.ColumnName = "TVSH";
dc5.ReadOnly = false;

DataColumn dc6 = new DataColumn();
dc6.DataType = System.Type.GetType("System.Decimal");
dc6.ColumnName = "Total";
dc6.Expression = "Price* QTY";//Multiplying the Price and Quantity DataColumns
dc6.ReadOnly = true;

DataColumn dc7 = new DataColumn();
dc7.DataType = System.Type.GetType("System.Decimal");
dc7.ColumnName = "WithoutVAT";
dc7.Expression = "Total/ VAT";//Multiplying the Price and Quantity DataColumns
dc7.ReadOnly = true ;

DataColumn dc9 = new DataColumn();
dc9.DataType = System.Type.GetType("System.Decimal");
dc9.ColumnName = "VATvalue";
dc9.Expression = "Total- WithoutVAT";//Multiplying the Price and Quantity DataColumns
dc9.ReadOnly = true ;

What should i change to make this work? Thanks

1 Reply

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Amit Gupta6y ago
First of all, the vat(or gst, vat is no more) 18% can be re-rewitten as 0.18 (18/100).
I discourage you to use computed columns because it will re calculate everytime you call it and can leads to performance degradation.
You should store the percentage amd its value seperately (like Gst and GstAmt) and store the actual value without any calculative methods.
If you can use above 3 steps then there is space for your issue.
If you still want to resolve at your step then you have to multiply the vat value with 100 in query or in code behind.