Oracle architecture

  • The size of the shared pool can be changed dynamically. The data dictionary cache of the shared pool holds the most recently accessed data dictionary information. The shared pool consists of a library cache and data dictionary cache.
  • Control file, redo log file, and data file are part of an Oracle database.
  • An SGA and Oracle background processes constitute an Oracle instance. An SGA is ended when an Oracle instance is shut down. Multiple users can share data in an SGA.
  • While making modifications in SPFILE, the instance should be in open and running state, whereas in the case of PFILE, the instance will have to be first shut down and restarted before making any modifications in it.
  • V is a dynamic performance view that is used to display the names and the location of all the control files.
  • Following is the correct sequence of the processes that occur when a database is opened:
    1. An initialization parameter file is read.
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New Features of Oracle 10g, Oracle 10g Installation, Server Configuration, and Maintenance of the Software

  • Memory – 512MB, Temp space – 400MB of free space in the /tmp directory applicable for the Unix operating system, Swap space – 1GB or twice the amount of RAM, Free disk space – 1.5GB are the minimum hardware requirements to install Oracle 10g.
  • The Installation Type list box is used to decide the type of installation.
  • Oracle Management Agent (OMA) is a centralized administrative tool that is capable of administering the database server and an application server.
  • The location (/u01/app/oracle) will be considered as the base of Optimal Flexible Architecture (OFA).
  • The password file is used to authenticate the administrative tasks from remote locations.
  • An Oracle 10g client can be used to connect to an Oracle 8i or 9i database by using the following syntax:
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Creating and Managing Microsoft Windows Services, Serviced Components, .NET Remoting Objects, and XML Web Services

  • The SessionID property of the HttpSessionState class identifies an active ASP.NET session by using a unique session ID.
  • The Process.Start method is used to start a Windows application and is registered in the system registry on a computer.
  • A constructor is used to create an object that is an instance of a class. It has the same name as the class in which it resides.
  • A sealed class is a class that cannot be derived from. Sealed classes are primarily used to prevent unintended derivation.
  • If a class derives from the ServiceBase class, the OnCustomCommand method is executed when the Service Control Manager (SCM) passes a custom command to the service. This method is used to specify actions when a command with the specified parameter value occurs.
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Creating User Services

  • The SessionID property of the HttpSessionState class identifies an active ASP.NET session by using a unique session ID.
  • The CodeBehind attribute specifies the name of the compiled file that contains the class associated with the page.
  • The @ Import directive is used to explicitly import a namespace into an ASP.NET application. The @ Implements directive is used to implement a specified .Net Framework interface in a Web page.
  • The ErrorPage attribute of the @ Page directive is used to set the URL if an unhandled exception occurs. Sam can set this target to the home page.
  • A Web page can be converted to a user control via code by the following manner:
    1. Change the extension of the Web page from .aspx to .ascx.
    2. Create an @ Control directive at the top of the page, instead of an @ Page directive.
    3. Remove the <html>, <head>, <body>, and <form> elements from the ASP.NET code.
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