SqlBulkCopy - The given value of type String from the data source cannot be converted to type int of the specified target column.

Problem

You execute the method WriteToServer, and the following error is thrown:

The given value of type String from the data source cannot be converted to type int of the specified target column.

var dt = new DataTable();
dt.Columns.Add("CustomerID", typeof(int));
dt.Columns.Add("Name");
dt.Columns.Add("Age");
			   
for(int i = 0; i < 1000; i++)
{
    dt.Rows.Add(i, "Name_" + i, "");
}	

using(var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServer()))
{
    connection.Open();
    
    using (var sqlBulk = new SqlBulkCopy(connection))
    {		
        sqlBulk.DestinationTableName = "Customers";
        sqlBulk.WriteToServer(dt);
    }
}

Try it

Solution

Cause

• You provided an empty value which cannot be converted to another type.

Fix

• ENSURE provided value is valid for the destination type.
• CREATE column by specifying the type to get the error before executing WriteToServer method.

Example

var dt = new DataTable();
dt.Columns.Add("CustomerID", typeof(int));
dt.Columns.Add("Name", typeof(string));
dt.Columns.Add("Age", typeof(int));
			   
for(int i = 0; i < 1000; i++)
{
    dt.Rows.Add(i, "Name_" + i, i);
}	

using(var connection = new SqlConnection(FiddleHelper.GetConnectionStringSqlServer()))
{
    // Make sure that connection is open
    connection.Open();
    
    using (var sqlBulk = new SqlBulkCopy(connection))
    {		
        sqlBulk.DestinationTableName = "Customers";
        sqlBulk.WriteToServer(dt);
    }
}

Try it