I found this beautiful article from CodeProject written by _Amy
Introduction
This is a small article explaining how to send an entire data-table to a Stored Procedure in the database server as an input parameter.
Background
It uses a logic which allows us to do add, modify, and delete operations on a set of records in the database using a simple form. The details also need to be shown after adding, updating, and deleting of records in a table. And the data-table should be given to a stored procedure to perform the operations. This feature will work with SQL Server 2008.
Advantages
- For each event on the page the form will not be interacting with the database. This reduces server round trips.
- All necessary operations such as:
- Inserting a new record
- Updating an existing record
- Deleting an existing record
are performed on client side only. They will be persisted in the database only after getting confirmation from the user. So, the performance of the application will improve.
- After performing a certain action (such as Insert, Update, or Delete) on the grid-view the data will be saved in “Session”. And whenever the data is required, it is be fetched from the Session.
- We send the entire data-table from the session to the database for manipulation, and with the use of a Stored Procedure we can do operations such as insert, delete, and update.
- It is easier to perform all operations on a set of rows at a time.
- The user can deal with thousands of data-rows at the same time without a connection.
- Extends the functionality of programming in a database engine.
Using the code
When a page is getting loaded the first time, data from the database is loaded to a data-table. In that data-table a column is added (named Operation). Whenever the user performs an action on the grid-view, the indicator bit is added to that column for that record (Insert 0, Update 1, and Delete 2). If the user clicks on a delete link on a particular row then the operation column of that row is updated to 2, and in the RowDataBound event of the grid-view we hide the records whose operation bit is 2. The temporary table is stored in session state. Before performing any operation, the session table will be called and the action will be performed on that table and again that table will be stored in the session. After performing all the necessary operations, when the user clicks on the Save button, the functionfnMangeOperations is called which will filter all the rows on which the operation was performed and the Save button will send only those details in which the operation has to be performed (you can find the functionfnMangeOperations in the source code from the attached files).
Step 1: Declaring global variables:
private clsEmpDetails _objEmpDetails;
private DataTable _dtEmpDetails;
private DataTable _dtEmpDetailsVals;
Step 2: Initializing the data members when page loads.
protected void Page_Load(object sender, EventArgs e)
{
if (!IsPostBack)
{
_objEmpDetails = new clsEmpDetails();
_dtEmpDetails = _objEmpDetails.fnGetDetails();
if(_dtEmpDetails != null){
_dtEmpDetails.Columns.Add("Operation", typeof(string));
Session["EmpDetails"] = _dtEmpDetails;
gvEmpDetails.DataSource = _dtEmpDetails;
gvEmpDetails.DataBind();
}
}
}
Just store the data in session and maintain the indicator for each operation. The operation will be like this:
protected void gvEmpDetails_RowCommand(object sender, GridViewCommandEventArgs e)
{
if (e.CommandName == "AddNew")
{
try{
_dtEmpDetails = Session["EmpDetails"] as DataTable;
string strID = (TextBox)gvEmpDetails.FooterRow.Cells[0].FindControl("txtInsID")).Text;
string strName = (TextBox)gvEmpDetails.FooterRow.Cells[1].FindControl("txtInsName")).Text;
string strAddress = (TextBox)gvEmpDetails.FooterRow.Cells[1].FindControl("txtInsAddress")).Text;
_dtEmpDetails.Rows.Add(strID, strName, strAddress, "0");
Session["EmpDetails"] = _dtEmpDetails;
fnBindEmpDetails(); }
catch(Exception ex){
}
}
}
On click of the Save button, call the following function by passing your DataTable as a parameter.
public string fnStoredProc(DataTable dtDetails)
{
string strMsg = "";
try
{
fnConOpen(); SqlCommand cmdProc = new SqlCommand("spEmpDetails", con);
cmdProc.CommandType = CommandType.StoredProcedure;
cmdProc.Parameters.AddWithValue("@Type", "InsertDetails");
cmdProc.Parameters.AddWithValue("@Details", dtDetails);
cmdProc.ExecuteNonQuery();
strMsg = "Saved successfully.";
}
catch (SqlException e) {
strMsg = e.Message.ToString();
}
finally
{
fnConClose();
}
return strMsg;
}
Procedure structure
First create a table type with matching columns which comes from the front-end. In this case:
CREATE TYPE EmpType AS TABLE
(
ID INT, Name VARCHAR(3000), Address VARCHAR(8000), Operation SMALLINT
)
Write the procedure for the operations.
ALTER PROCEDURE spEmpDetails
@Type VARCHAR(15),
@Details EmpType READONLY
AS
BEGIN
IF(@Type='FetchDetails')
SELECT * FROM EmployeeDetails
ELSE
BEGIN
DELETE FROM EmployeeDetails WHERE ID IN(SELECT ID FROM @Details WHERE Operation=2)
UPDATE e SET e.Name=d.Name, e.Address=d.Address FROM EmployeeDetails e, @Details d
WHERE d.ID=e.ID and d.Operation=1
INSERT INTO EmployeeDetails(ID, Name, Address)
SELECT ID, Name, Address FROM @Details WHERE Operation=0;
END
END
GO
Note: This procedure takes a datatabe as its parameter and performs insert, update, and delete operations based on the table data.
