Populating a DataSet with Multiple Tables Using DataReader
In this article, we'll address the challenge of filling a DataSet consisting of multiple tables using a DataReader, maintaining the one-to-many relationship between them.
The provided code sample demonstrates the use of a DataReader to fill a DataSet with one table. To extend this functionality to multiple tables, we propose a two-pronged approach:
Option 1: Multiple Queries
Send separate queries to retrieve data from each table, mapping the generated Table names to those desired in the DataSet.
Option 2: Single Query with Multiple SELECT Statements
Craft a single query containing multiple SELECT statements, enabling the database server to process all requests in a single go. However, keep in mind that the resulting tables will be assigned default names (e.g., Table, Table1), which can be explicitly mapped to the intended names using the TableMappings property of the SqlDataAdapter class.
Here's an example demonstrating the second approach:
SqlDataAdapter adapter = new SqlDataAdapter( "SELECT * FROM Customers; SELECT * FROM Orders", connection); adapter.TableMappings.Add("Table", "Customer"); adapter.TableMappings.Add("Table1", "Order"); adapter.Fill(ds);
By utilizing either of these techniques, you can effectively populate a DataSet with multiple tables using a DataReader while preserving their inter-table relationships.
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