In client-server technology, the client is responsible for business logic and presentation
of data to the user whereas the server manages database and allocate memory, network
bandwidth and disk operations among the request sent by the client (Alexis and
Mathews, 1999). The project is implemented in two departments of Mizoram University.
Both client and server are placed in the same machine for the primary developmental
purposes. README_BUTTERFLYDB.txt file gives the guidelines for the user about
installation of software and application. It is made mandatory to restore the
Mizoram_Butterfly database at every new installation of this application. In general,
data are inserted and existing data are removed to have the current copy of the
database; the backup database mechanism is implemented through VB.NET. Furthermore,
the backup can safeguard against unexpected data loss or during application errors
(Gary and James, 1996). During the developmental phase, much care is taken to produce
this application under a high user-friendly environment as it is going to be handled by
biologists independently.
VB.NET is a productive language and tool to build windows-based and web-based
applications and it has powerful Integrated Development Environment (IDE). The
applications can be deployed and maintained with high efficiency and ease. The current
application has adopted ADO.NET for data storage and retrieval from database (SQL
server 2000) as this database server is designed with priority for .NET based applications
(Thearon and Bryan, 2006). In ADO.NET architecture, the DataSet are created from
database using .Net data provider commands (Figure 1). The key features of ADO.NET are
memory management, security and exception handling.
The data access in ADO.NET relies on two significant components: Data provider and
Dataset. Data provider is the primary source for providing and maintaining the
connection between VB.NET (Client) and SQL Server (Server). The .NET framework has
two data providers—SQL data provider and OleDb data provider (Tim, 2008). This project
has utilized SQL data provider to establish the connection between Client and Server
using component class
When the user requests a connection from VB.NET, database server ensures that
login exists in the SYSLOGINS system table of the Master database in SQL Server and
given password matches with previously defined password (Rajesh, 2006). Herein, the
connection object is local/localhost because the VB.NET (Client) and SQL Server (Server)
are installed on the same PC. The name of database trying to connect and
authentication information such as user ID and password are also passed to connection
string to access the data source
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