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SqlBulkCopyColumnMapping Class

SqlBulkCopyColumnMapping Class

Defines the mapping between a column in a SqlBulkCopy instance's data source and a column in the instance's destination table.


Namespace:  System.Data.SqlClient
Assembly:  System.Data (in System.Data.dll)

public sealed class SqlBulkCopyColumnMapping

The SqlBulkCopyColumnMapping type exposes the following members.

Public methodSqlBulkCopyColumnMapping()Default constructor that initializes a new SqlBulkCopyColumnMapping object.
Public methodSqlBulkCopyColumnMapping(Int32, Int32)Creates a new column mapping, using column ordinals to refer to source and destination columns.
Public methodSqlBulkCopyColumnMapping(Int32, String)Creates a new column mapping, using a column ordinal to refer to the source column and a column name for the target column.
Public methodSqlBulkCopyColumnMapping(String, Int32)Creates a new column mapping, using a column name to refer to the source column and a column ordinal for the target column.
Public methodSqlBulkCopyColumnMapping(String, String)Creates a new column mapping, using column names to refer to source and destination columns.

Public propertyDestinationColumnName of the column being mapped in the destination database table.
Public propertyDestinationOrdinalOrdinal value of the destination column within the destination table.
Public propertySourceColumnName of the column being mapped in the data source.
Public propertySourceOrdinalThe ordinal position of the source column within the data source.

Public methodEquals(Object)Determines whether the specified object is equal to the current object. (Inherited from Object.)
Public methodGetHashCodeServes as the default hash function. (Inherited from Object.)
Public methodGetTypeGets the Type of the current instance. (Inherited from Object.)
Public methodToStringReturns a string that represents the current object. (Inherited from Object.)

Column mappings define the mapping between data source and the target table.

If mappings are not defined—that is, the ColumnMappings collection is empty—the columns are mapped implicitly based on ordinal position. For this to work, source and target schemas must match. If they do not, an InvalidOperationException will be thrown.

If the ColumnMappings collection is not empty, not every column present in the data source has to be specified. Those not mapped by the collection are ignored.

You can refer to source and target columns by either name or ordinal. You can also mix by-name and by-ordinal column references in the same mappings collection.

The following example bulk copies data from a source table in the AdventureWorks sample database to a destination table in the same database. Although the number of columns in the destination matches the number of columns in the source, and each destination column is in the same ordinal position as its corresponding source column, the column names do not match. SqlBulkCopyColumnMapping objects are used to create a column map for the bulk copy.

Important noteImportant

This sample will not run unless you have created the work tables as described in Bulk Copy Example Setup. This code is provided to demonstrate the syntax for using SqlBulkCopy only. If the source and destination tables are in the same SQL Server instance, it is easier and faster to use a Transact-SQL INSERT … SELECT statement to copy the data.

using System.Data.SqlClient;

class Program
    static void Main()
        string connectionString = GetConnectionString();
        // Open a sourceConnection to the AdventureWorks database. 
        using (SqlConnection sourceConnection =
                   new SqlConnection(connectionString))

            // Perform an initial count on the destination table.
            SqlCommand commandRowCount = new SqlCommand(
                "SELECT COUNT(*) FROM " +
            long countStart = System.Convert.ToInt32(
            Console.WriteLine("Starting row count = {0}", countStart);

            // Get data from the source table as a SqlDataReader.
            SqlCommand commandSourceData = new SqlCommand(
                "SELECT ProductID, Name, " +
                "ProductNumber " +
                "FROM Production.Product;", sourceConnection);
            SqlDataReader reader =

            // Set up the bulk copy object. 
            using (SqlBulkCopy bulkCopy =
                       new SqlBulkCopy(connectionString))
                bulkCopy.DestinationTableName =

                // Set up the column mappings by name.
                SqlBulkCopyColumnMapping mapID =
                    new SqlBulkCopyColumnMapping("ProductID", "ProdID");

                SqlBulkCopyColumnMapping mapName =
                    new SqlBulkCopyColumnMapping("Name", "ProdName");

                SqlBulkCopyColumnMapping mapMumber =
                    new SqlBulkCopyColumnMapping("ProductNumber", "ProdNum");

                // Write from the source to the destination. 
                catch (Exception ex)
                    // Close the SqlDataReader. The SqlBulkCopy 
                    // object is automatically closed at the end 
                    // of the using block.

            // Perform a final count on the destination  
            // table to see how many rows were added. 
            long countEnd = System.Convert.ToInt32(
            Console.WriteLine("Ending row count = {0}", countEnd);
            Console.WriteLine("{0} rows were added.", countEnd - countStart);
            Console.WriteLine("Press Enter to finish.");

    private static string GetConnectionString()
        // To avoid storing the sourceConnection string in your code,  
        // you can retrieve it from a configuration file. 
        return "Data Source=(local); " +
            " Integrated Security=true;" +
            "Initial Catalog=AdventureWorks;";

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.
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