You should add a ConnectionStrings element in your Web.config file. The samle connection string for Oracle database might look like the following:

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<add name=”OracleConnectionString”
  connectionString=”Data Source=OracleS;Persist 
  Security Info=True;Password=”******”;User ID=Test”
  providerName=”System.Data.OracleClient” />

  •  name  – set the value to the name that you want to use to reference the connection string.
  • connectionString – assign the connection string that is required to connect to the Oracle database.
  • providerName – assign the value “System.Data.OracleClient”, which specifies that ASP.NET should use the ADO.NET System.Data.OracleClient provider when making a connection with this connection string.