Low cost ecommerce web development India flash website design

The ConnectionString

After setting the mode, you must set the Connection object's

ConnectionString property. Although you must set this property each time

you open a new Connection object, you should define the connection string

(or strings) in your application's global.asa file as an application-level or

session-level variable. There are at least three reasons to define the connection

string in the global.asa file; it means you only have one place to check for

connection string problems, you can change the connection from one database

to another with minimal code changes during development, and you can copy

or move your application from one server to another very quickly.

The ConnectionString property is both simple and complicated. It has

several parts, all of which are optional, depending on which type of

connection string you're using, but typically, you specify the following:

§ Provider name

§ Name of the database server

§ Name of the database you want to use

§ User ID (UID) with which to connect

§ Password (PWD) for that user ID.

59

You separate the parts of the connection string with semicolons. For example,

at the simplest level, you can use an Open Database Connectivity (ODBC)

Data Source Name (DSN), a user ID, and password to connect to your

database. A DSN already contains the provider, the database server, and the

database name, so you don't have to specify those again.

For example:

Dim Conn

Set Conn = Server.Create0bject(“ADODB.Connection")

Conn.Mode = adModeReadWrite

Conn.ConnectionString = “DSN=myDSN;UID=manas;PWD=manas;"

Unfortunately, that's not the best method. By default, ODBC DSNs use the

MSDASQL provider, but the JET OLEDB provider is faster and provides

more functionality. Use this type of connection string instead.

Dim Conn, ConnStr

ConnStr= "PROVIDER=Microsoft.Jet.OLEDB.4.0;DATA SOURCE=" +

Server.MapPath(Path2DB)

Set Conn = Server.CreateObject(“ADODB.Connection")

Conn.Mode = adModeReadWrite

Conn.ConnectionString = ConnStr

The connection string contains the provider name, the name of the server (in

this case, and the path to the MDB file. We use the Server.MapPath function

to translate the virtual path to the actual path on the server's disk. For

example, a database at the location

http://www.manastungare.com/users.mdb

can actually be the file

E:\Web\Databases\users.mdb

Server.MapPath translates the first address to the second (which is what is

needed by the ADODB.Connection object.)

You must set most of the Connection object's properties before opening the

connection. If you later want to change a property, close the connection,

change the property value, and then reopen the connection.

To open a connection, use the Open method of the Connection object.

Conn.Open

If the Open method executes without errors, you have a working connection

to the database.

60

All the procedures so far can be simplified with an alternate syntax. The Open

method accepts up to four optional arguments: a ConnectionString, a user ID,

a password, and the Options argument consisting of a ConnectOptionEnum

constant.

Conn.Open ConnStr, "manas", "manas", adAsyncConnect

You can specify more than one value for the options by adding the constants

together.

freelance web designer India web development

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73