如何在SQL Server表中插入包含Null值的DataTable？

Question

I have a DataTable which also contains some Null values such as

   ID             CustomerID           CompanyID
 -------        --------------       --------------
   1                  2                  Null
   2                 Null                1
   3                  5                  4

I want to insert this DataTable into a Table. In SQL Server 2005, I have one Table called "JobDetails" which has three columns "JobOrderID", "CustomerID" and "CompanyID". So the above DataTable to be inserted into the "JobDetails" table like follows:

   JobOrderID      CustomerID          CompanyID
  ------------    ------------        ------------
       1               2                Null
       2              Null                1
       3               5                  4

How to achieve this? I tried to pass the DataTable as XML. But due to the presence of NUll values it throws error not inserting.

Error means, the XML tags not considering the NULL values, so it takes as

  <NewDataSet>
      <JobDetails> 
          <JobOrderID>1</JobOrderID>
          <CustomerID>2</CustomerID>
      </JobDetails>
      <JobDetails> 
          <JobOrderID>2</JobOrderID>
          <CompanyID>1</CompanyID>
      </JobDetails>
      <JobDetails> 
          <JobOrderID>3</JobOrderID>
          <CustomerID>5</CustomerID>
          <CompanyID>4</CompanyID>
      </JobDetails>
  </NewDataSet>

It neglects the tags which contains NULL. So the insertion not takes place.

Answer 1

Normally you would insert from a DataTable via an adapter (such as System.Data.SqlClient.SqlDataAdapter ). This will handle the nulls etc. You could also use SqlBulkCopy if it is very large (although you need to be careful about transaction logs etc in that case, as a bulk insert might not be fully logged, IIRC).

caveat: personally, I would be using a DataTable here anyway - I'd be using regular typed classes.

Answer 2

In a case to get a DataTable into another table, use the SqlBulkCopy class. Ensure your values that are null are set to DBNull.Value as opposed to 'null' and use the SqlBulkCopy to set the destination table name

using (SqlBulkCopy bulkCopy = new SqlBulkCopy(connection))
{
   bulkCopy.DestinationTableName = destinationTableName;
   bulkCopy.WriteToServer(yourDataTable);
}

Answer 3

I think it would be easier if you follow the method described in the following article:

Use DataTable to update table in Database

Answer 4

I think you can replace NULL with their default value for ex. in companyId field NULL replace with -1 or 0 and in SQL Server you can again replace -1 or o to NULL .

Through replacing ID will be part of XML . I know it is not good solution.