Update SQL table very slow - sql

Question

I have problem when I try to update SQL table with
I have datagridview and I need to update SQL table and take the value form my datagridview . my datagridview have more than 10000 rows
I take time more than 1:30 hour very slow
datagridview name "dgv_balance"
Here is the code:
using (SqlConnection cn = new SqlConnection())
{
cn.ConnectionString = "My Connection"
cn.Open();
using (SqlCommand cmd_select = new SqlCommand())
{
for (int i = 0; i < dgv_balance.RowCount; i++)
{
cmd_select.Connection = cn;
cmd_select.CommandType = CommandType.StoredProcedure;
cmd_select.CommandText = "clients_balances_select_glid_date";
cmd_select.Parameters.AddWithValue("#glid", Convert.ToString(dgv_balance.Rows[i].Cells[0].Value));
cmd_select.Parameters.AddWithValue("#date", Convert.ToDateTime(dgv_balance.Rows[i].Cells[2].Value));
if (cmd_select.ExecuteScalar().ToString()=="")
{
using (SqlCommand cmd_insert = new SqlCommand())
{
cmd_insert.Connection = cn;
cmd_insert.CommandType = CommandType.StoredProcedure;
cmd_insert.CommandText = "clients_balances_insert_data";
cmd_insert.Parameters.AddWithValue("#glid", Convert.ToString(dgv_balance.Rows[i].Cells[0].Value));
cmd_insert.Parameters.AddWithValue("#name", Convert.ToString(dgv_balance.Rows[i].Cells[1].Value));
cmd_insert.Parameters.AddWithValue("#date", Convert.ToString(dgv_balance.Rows[i].Cells[2].Value));
cmd_insert.Parameters.AddWithValue("#balance", Convert.ToString(dgv_balance.Rows[i].Cells[3].Value));
cmd_insert.ExecuteNonQuery();
cmd_insert.Parameters.Clear();
}
}
else
{
using (SqlCommand cmd_update= new SqlCommand())
{
cmd_update.Connection = cn;
cmd_update.CommandType = CommandType.StoredProcedure;
cmd_update.CommandText = "clients_balances_update_balance";
cmd_update.Parameters.AddWithValue("#glid", Convert.ToString(dgv_balance.Rows[i].Cells[0].Value));
cmd_update.Parameters.AddWithValue("#date", Convert.ToString(dgv_balance.Rows[i].Cells[2].Value));
cmd_update.Parameters.AddWithValue("#balance", Convert.ToString(dgv_balance.Rows[i].Cells[3].Value));
cmd_update.ExecuteNonQuery();
cmd_update.Parameters.Clear();
}
}
cmd_select.Parameters.Clear();
}
}
}

Answer 1

You may have to call SELECT command for one time only before you loop through your datagridview rows and cache the result data and check on the result while iterating your datagridview instead of calling it on each row. This way you will reduce your commands by 10000.
It also better if you could show us your procedures' queries.
Or if your datagridview is the ONLY source for your data then you can delete all your previous data in your database and make one insert call for all of your datagridview data.
Try this:
using (SqlConnection cn = new SqlConnection())
{
cn.ConnectionString = "MyConnection" ;
cn.Open();
SqlDataAdapter da = new SqlDataAdapter();
DataTable dt = new DataTable();
using (SqlCommand cmd_select = new SqlCommand())
{
cmd_select.Connection = cn; cmd_select.CommandType = CommandType.StoredProcedure; cmd_select.CommandText = "clients_balances_select_glid_date";
da.SelectCommand = cmd_select;
da.Fill(dt);
for (int i = 0; i < dgv_balance.RowCount; i++)
{
if(/* check here if dt contains this row*/)
{
// Insert
}
else
{
// Update
}
}
}
}

Answer 2

I think you should insert or update all data one time.
Create index for glId column. If glId is primary key, it's indexed.
Assumes that List ClientBalance is list items you need update or insert.
public class ClientBalance
{
GlId int {get;set;}
ClientName string {get;set;}
Balance decimal {get;set;}
DateInput DateTime {get;set;}
}
You could serialize list Item to xml string and pass it to store procedure
public string Serialize<T>(T value) where T : new()
{
var serializeXml = string.Empty;
if (value != null)
{
try
{
var xmlserializer = new XmlSerializer(typeof(T));
var stringWriter = new StringWriter();
var writer = XmlWriter.Create(stringWriter);
xmlserializer.Serialize(writer, value);
serializeXml = stringWriter.ToString();
writer.Close();
}
catch (Exception ex)
{
return string.Empty;
}
}
return serializeXml;
}
Create a new store procedure for insert or update item like that:
CREATE PROCEDURE [dbo].[clients_balances_insert_or_update]
(
#xmlObject nvarchar(max)
)
AS
BEGIN
-- TABLE INCLUDE DATE FROM XML
DECLARE #tblBalances AS TABLE
(
GlId int,
DateInput datetime,
ClientName nvarchar(50),
Balance decimal(18,2)
)
DECLARE #idoc int -- xml id
-- PARSE XML TO OBJECT
EXEC sp_xml_preparedocument #idoc OUTPUT, #xmlObject
INSERT INTO #tblBalances
(
GlId, DateInput, ClientName, Balance
)
SELECT s.GlId, s.DateInput, s.ClientName, s.Balance
FROM OPENXML (#idoc, '/ArrayOfClientBalance/ClientBalance', 8) WITH (
GlId int 'GlId',
DateInput datetime 'DateInput',
ClientName NVARCHAR(50) 'ClientName',
Balance DECIMAL(18,2) 'Balance'
) s
EXEC sp_xml_removedocument #idoc
-- USE MERGE FOR INSERT OR UPDATE DATE
-- Use transaction
BEGIN TRAN InsertOrUpdate
BEGIN TRY
MERGE Target AS T
USING #tblBalances AS S
ON (T.GlId = S.GlId)
WHEN NOT MATCHED BY TARGET
THEN INSERT( GlId, DateInput, ClientName, Balance) VALUES( GlId, DateInput, ClientName, Balance)
WHEN MATCHED
THEN UPDATE SET DateInput = S.DateInput, Balance = s.Balance
COMMIT TRAN InsertOrUpdate;
END TRY
BEGIN CATCH
ROLLBACK TRAN InsertOrUpdate;
THROW;
END CATCH
END
Hope this helpfully!