2. ADO .NET
ADO.NET is an OO framework that allows
you to interact with DBs
Can use ADO.NET through code, or by using
bounded controls
ADO.NET extremely flexible and efficient
3. ADO.NET
Previously applications would talk to Database
using SQL
The application would be constantly connected
to the DB
We still use SQL but the data is disconnected
It will connect to a database server when it
needs to run a query and then disconnects
immediately
ADO.NET still provides the connection
oriented traditional approach.
4. Traditional Data Access
Architecture
1. Makes a Connection
2. Pass some query to DB and reads result
3. Pass another query to DB and reads result
4. Disconnects from DB System
5. ADO.NET Disconnected Model
1. Make a connection
2. Pass query and gets back result
3. Disconnects
4. Makes connection again
5. Passes another query and gets result
6. Disconnects from the DB
6. ADO.NET
Keeps a local virtual copy of the database in
your application
All of the generic classes for data access are
stored in the System.Data Namespace.
7. ADO.NET
ADO.NET uses managed providers to
connect to databases
Managed providers allow fast data streams
from databases
Deals with security such as database locks,
passwords etc.,
8. Main Components of ADO.NET
Object Description
Connection Creates a connection to the data
source
Command Provides access to commands
that can be executed against the
data source
DataAdapter Serves as an ambassador
between your dataset and
datasource, maps instructions
between the two
DataSet Provides an in-memory
representation of your data source
DataReader Read-Only forward stream
containing your data
9. Advantages
Interoperability
Data is transported as XML
Can be read by anyone on any platform
Scalability
Client Server model is gone
ADO promotes the use of disconnected datasets
Productivity
Quicker
Less Bugs
10. Advantages Cont’d
Performance
Disconnected datasets
Database Server is no longer a bottleneck
Performance boost
Concurrency
Database not locked out all the time
11. Using ADO.NET in Code
1. Set up your objects
2. Connect to DB using connection object
3. Set up the data adapter
4. Copy data from data adapter to Dataset
18. Doing it In Code
An access Database Table
It will be represented in our DataSet as a Table
The first table is given an index of 0
The first row in the table has an index value of 0
also
The first column has a value of 0
32. The Code – Displaying the
DataSet Contents
Point a textbox to a row and column of the dataset
Table
Point a DataGrid control at a DataSet
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34. Point a textbox to a row and column of the dataset
Table
Point a DataGrid control at a DataSet
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.