Using VistaDB with ADO.NET - Common Operations using VistaDB Exclusively
The following code examples show how to perform common data operations using ADO.NET in a VistaDB-exclusive manner; Developers are encouraged to use the alternate approach that uses Database Factory objects since it will work for VistaDB and SQL Server without any code changes.
This code sample shows the basic step of opening a VistaDB database.
using (VistaDBConnection connection = new VistaDBConnection())
{
connection.ConnectionString = @"Data Source=C:\mydatabase.vdb6";
connection.Open();
}
Using connection As New VistaDBConnection()
connection.ConnectionString = "Data Source=C:\mydatabase.vdb6"
connection.Open()
End Using
Most database operations require creating a DbCommand object, configuring it for your operation, and associating it with a database connection to work with. This example shows creating the connection and command and associating them together.
using (VistaDBConnection connection = new VistaDBConnection())
{
connection.ConnectionString = @"Data Source=C:\mydatabase.vdb6";
connection.Open();
using (VistaDBCommand command = new VistaDBCommand())
{
command.Connection = connection;
}
}
Using connection As New VistaDBConnection()
connection.ConnectionString = "Data Source=C:\mydatabase.vdb6"
connection.Open()
Using command As New VistaDBCommand()
command.Connection = connection
End Using
End Using
Inserting Data Using a Command
In this example the command is being used to execute a simple TSQL insert. Since no data set is expected in return the ExecuteNonQuery() method is used to execute the command.
using (VistaDBConnection connection = new VistaDBConnection())
{
connection.ConnectionString =@"Data Source=C:\mydatabase.vdb6";
connection.Open();
using (VistaDBCommand command = new VistaDBCommand())
{
command.Connection = connection;
command.CommandText = "INSERT INTO MyTable (MyColumn) VALUES ('Test')";
command.ExecuteNonQuery();
}
}
Using connection As New VistaDBConnection()
connection.ConnectionString = "Data Source=C:\mydatabase.vdb6"
connection.Open()
Using command As New VistaDBCommand()
command.Connection = connection
command.CommandText = "INSERT INTO MyTable (MyColumn) VALUES ('Test')"
command.ExecuteNonQuery()
End Using
End Using
Inserting Data Using a Parameterized Command
In this example the command is being used to execute a simple TSQL insert. It improves on the previous example by using a parameterized TSQL statement and ADO.NET Parameters to pass data. It is highly recommended that parameters always be used to pass data from your application to ADO.NET for reliability, consistency, and to ensure there is no possibility of a SQL Injection Attack against your code.
using (VistaDBConnection connection = new VistaDBConnection())
{
connection.ConnectionString = @"Data Source=C:\mydatabase.vdb6";
connection.Open();
using (VistaDBCommand command = new VistaDBCommand())
{
int Age = 21;
command.Connection = connection;
command.CommandText = "INSERT INTO MyTable (MyColumn) VALUES (@age)";
command.Parameters.Add("@age", Age);
command.ExecuteNonQuery();
}
}
Using connection As New VistaDBConnection()
connection.ConnectionString = "Data Source=C:\mydatabase.vdb6"
connection.Open()
Using command As New VistaDBCommand()
Dim Age As Integer = 21
command.Connection = connection
command.CommandText = "INSERT INTO MyTable (MyColumn) VALUES (@age)"
command.Parameters.Add("@age", Age)
command.ExecuteNonQuery()
End Using
End Using
Querying Data and Filling a Data Table
To retrieve multiple rows of data from a database ADO.NET uses a TableAdapter to fill a DataTable. The DataTable can have exactly one set of rows with a common schema.
using (VistaDBConnection connection = new VistaDBConnection())
{
connection.ConnectionString = @"Data Source=C:\mydatabase.vdb6";
connection.Open();
DataTable table = new DataTable();
using (VistaDBCommand command = new VistaDBCommand())
{
command.Connection = connection;
command.CommandText = "SELECT * FROM MyTable";
using (VistaDBDataAdapter adapter = new VistaDBDataAdapter())
{
adapter.SelectCommand = command;
adapter.Fill(table);
}
}
}
Using connection As New VistaDBConnection()
connection.ConnectionString = "Data Source=C:\mydatabase.vdb6"
connection.Open()
Dim table As New DataTable()
Using command As New VistaDBCommand()
command.Connection = connection
command.CommandText = "SELECT * FROM MyTable"
Using adapter As New VistaDBDataAdapter()
adapter.SelectCommand = command
adapter.Fill(table)
End Using
End Using
End Using
Calling Stored Procedures
Like Microsoft SQL Server, VistaDB supports Stored Procedures. In this example the stored procedure "CalcSalesTax" is being called with several parameters. To prevent SQL Injection attacks parameterized commands should be used to pass data to stored procedures instead of attempting to assemble the query as a string.
using (VistaDBConnection connection = new VistaDBConnection())
{
connection.ConnectionString = @"Data Source=C:\mydatabase.vdb6";
connection.Open();
using(VistaDBCommand command = new VistaDBCommand("CalcSalesTax", connection))
{
command.CommandType = CommandType.StoredProcedure;
VistaDBParameter param = command.Parameters.AddWithValue("@SalesTotal", 100.00);
param.Direction = ParameterDirection.Input;
param.DbType = System.Data.DbType.Currency;
VistaDBParameter outparam = command.Parameters.Add("@OrderTotal", VistaDBType.Money);
outparam.Direction = ParameterDirection.Output;
command.ExecuteNonQuery();
}
}
Using connection As New VistaDBConnection()
connection.ConnectionString = "Data Source=C:\mydatabase.vdb6"
connection.Open()
Using command As New VistaDBCommand("CalcSalesTax", connection)
command.CommandType = CommandType.StoredProcedure
Dim param As VistaDBParameter = command.Parameters.AddWithValue("@SalesTotal", 100.0)
param.Direction = ParameterDirection.Input
param.DbType = System.Data.DbType.Currency
Dim outparam As VistaDBParameter = command.Parameters.Add("@OrderTotal", VistaDBType.Money)
outparam.Direction = ParameterDirection.Output
command.ExecuteNonQuery()
End Using
End Using