Tuesday 27 December 2011

Advantege of using Database Management System(DBMS)......

Warehouse of Information

  • The database management systems are warehouses of information, where large amount of data can be stored. The common examples in commercial applications are inventory data, personnel data, etc. It often happens that a common man uses a database management system, without even realizing, that it is being used. The best examples for the same, would be the address book of a cell phone, digital diaries, etc. Both these equipment store data in their internal database.



Defining Attributes

  • The unique data field in a table is assigned a primary key. The primary key helps in the identification of data. It also checks for duplicates within the same table, thereby reducing data redundancy. There are tables, which have a secondary key in addition to the primary key. The secondary key is also called 'foreign key'. The secondary key refers to the primary key of another table, thus establishing a relationship between the two tables. 



Systematic Storage

  • The data is stored in the form of tables. The tables consist of rows and columns. The primary and secondary key help to eliminate data redundancy, enabling systematic storage of data.



Changes to Schema

  • The table schema can be changed and it is not platform dependent. Therefore, the tables in the system can be edited to add new columns and rows without hampering the applications, that depend on that particular database.



No Language Dependence

  • The database management systems are not language dependent. Therefore, they can be used with various languages and on various platforms. 



Table Joins

  • The data in two or more tables can be integrated into a single table. This enables to reduce the size of the database and helps in easy retrieval of data.



Multiple Simultaneous Usage

  • The database can be used simultaneously by a number of users. Various users can retrieve the same data simultaneously. The data in the database can also be modified, based on the privileges assigned to users.



Data Security

  • Data is the most important asset. Therefore, there is a need for data security. Database management systems help to keep the data secured.



Privileges

  • Different privileges can be given to different users. For example, some users can edit the database, but are not allowed to delete the contents of the database.



Abstract View of Data and Easy Retrieval

  • DBMS enables easy and convenient retrieval of data. A database user can view only the abstract form of data; the complexities of the internal structure of the database are hidden from him. The data fetched is in user-friendly format. 



Data Consistency

  • Data consistency ensures a consistent view of data to every user. It includes the accuracy, validity and integrity of related data. The data in the database must satisfy certain consistency constraints, for example, the age of a candidate appearing for an exam should be of number datatype and in the range of 20-25. When the database is updated, these constraints are checked by the database systems.



The commonly used database management system is called relational database management system (RDBMS). The most important advantage of database management systems is the systematic storage of data, by maintaining the relationship between the data members. The data is stored as tuples in a RDBMS. 


The advent of object-oriented programming gave rise to the concept of object oriented database management systems. These systems combine properties like inheritance, encapsulation, polymorphism, abstraction with atomicity, consistency, isolation and durability, also called ACID properties of DBMS.


Database management systems have brought about systematization in data storage, along with data security.

How to create a database by using Microsoft Access 2007???


  • To begin, open Microsoft Access. The instructions and images in this article are for Microsoft Access 2007. If you're using a different version of Access, they may vary slightly.
  • Next, you'll need to create a blank database to use as your starting point. Click "Blank Database" on the Getting Started with Microsoft Office Access screen to begin this process, as shown in the figure below.

  • In the next step, the right pane of the Getting Started window will change to match the image above. Give your database a name by typing it into the text box and click the Create button to begin building your database.


  • Access will now present you with a spreadsheet-style interface, shown in the image above, that helps you create your database tables. 
  • The first spreadsheet will help you create your first table. As you can see in the image above, Access begins by creating an Auto Number field named ID that you can use as your primary key. To create additional fields, simply double-click on the top cell in a column (the row with a darker blue shade) and type the name of the field into that cell. When you've finished typing in the field name, press Enter. You can then use the Data Type and Format controls in the Ribbon to customise the field. 
  • Continue adding fields in this same manner until you've created your entire table. Once you've finished building the table, click the Save icon on the Quick Access toolbar. Access will then ask you to provide a name for your table. You can also create additional tables by selecting the Table icon in the Create tab of the Access Ribbon. 





    This is the video of tutorial Microsoft Access 2007 ^^

    Adobe Photoshop CS3 Tutorial

    using Adobe Photoshop can let ur picture becum more nice and also can attract the people^^
    that is the simple introduction to introduce how to use the adobe photoshop:


    This is the video about Adobe Photoshop CS3

    Simple Way to using Adobe Photoshop :

    1. Open a digital photo in Cs3. Save a copy of the photo with a different name because you will want to work on the copy without touching the original. First, tone the photo to your preferences. You can use presets.
    2. Go to Image > Auto Tone, Auto Contrast or Auto Color. For most evenly exposed photos, these presets will do a serviceable job. For more dynamic variation than the presets, open the "Info" box. Go to Window > Info. This palette will show you the percentages of each color as you move the mouse around the photo.
    3. Go to Image > Adjustments > Levels. Below the "Options" button on the right are three eye droppers for, from left, blacks, midtones and whites. Select the black eyedropper and find the darkest area of the image. The Info palette will show you light to dark ranges for red, green and blue or cyan, magenta, yellow and black (K). The higher the number of K, the more black there is in that area of the image. Using the black eyedropper, find the blackest area of the image and click. Then click the white eyedropper and find the whitest area. This will be close to zero on the Info palette. When you find it, click it. This generally will give a balanced tone, but you can tweak it with the sliders under the histogram graph. The left one is black, middle is midtones and right is white.
    4. Use "Shadow/Highlights" or "Curves" to tweak the tone further. If the image has stark contrast and some of the detail is lost, "Shadow/Highlights" will punch up the shadows without touching the highlights, or vice versa. With "Curves," you set a brightness in the center, then tweak the lights and darks on the sides.
    5. Other controls under Image > Adjustments, such as "Brightness/Contrast," "Exposure" and "Variations" also allow manipulation of tone. "Variations" is not as subtle as some of the others, but you can compare variations of the image with different colors added or subtracted to the image.
    6. Resize your photo depending on how you intend to use it. For example, an image intended for a website only needs a resolution of 72 dots per inch. If you plan to print the image, it should be at a minimum of 200 dots per inch (dpi). The more dpi resolution you choose, the finer the quality of the final image, but the bigger the file. To resize an image to 8 1/2-by-11 inches, go to Image > Image Size. In the pop-up menu, use the bottom portion. If it's a horizontal or "landscape" image, set the width to 11 inches. The height will reset automatically. Then go to "Resolution" and set it at 300 dpi.
    7. .Print the image. Go to File > Print. In the pop-up menu, select the printer and make adjustments. The default is for a vertical ("portrait") image, so if you need horizontal, click that button next to the "Page Setup" button. You will see how the image will look when printed. Click "Print." A pop-up menu will appear where you can set specifics for the printer. These settings will produce the best image on any paper. For a photo, choose a top-quality photo setting.
    8. Experiment. There is a lot more to Photoshop than just toning photos. Go to Window > Actions for some presets. Try "Soft Posterize," "Sepia (Layer)" or "Fluorescent Chalk." You also can try things in the Filter Gallery (Filter > Filter Gallery). A photo can look like a painting. You can make it into "Stationary" or use "Chrome" or "Bas Relief."

    Uses of Adobe Photoshop

    Why we need using Adobe Photoshop CS3???why?
    That is because Adobe Photoshop can create many things....
    There are the uses of Adobe Photoshop CS3 :

    History and Significance

    • Released in late 2006, Photoshop CS3 was Adobe's 10th version of graphics editing software, preceding Adobe's release of CS4 in 2008. Uses for Photoshop CS3 are limitless thanks to CS3 upgrades from its predecessor, CS2. Adobe added extra features, like Adobe Bridge, which provides easy access to media files, smart filters that enable changeable filters and advanced animating tools.

    Image Editing

    • Photo editing is the most obvious of uses for Photoshop CS3. With many mode adjustments, such as photo filters, true black and white capabilities, and hue saturation controls, Photoshop is ideal for photographers of any experience level. Photoshop has several functions ideal for image editing such as color balance, highlight and contrast tools, quick masks, healing and red eye removal functions, and cloning functions to heal faded or damaged photos.

    Creating Art

    • One of the most incredible uses for Photoshop CS3 is the ability to create artistic pieces. Aside from editing tools, Photoshop CS3 features hundreds of different brush options. Some of these brush styles are wet and dry media, calligraphic, drop shadow, natural and faux finish. Photoshop CS3 enables the use of layers with several different blending modes and filter galleries to add certain effects like grain or underlayment.

    Animation and 3D

    • A surprising use for Photoshop CS3 is the ability to animate pictures. Photoshop CS3 features frame animation and timeline functions. Both functions allow optimization of the layers involved in the animation. Frame animating involves editable layers that move and change to display animation. Timeline animating involves a slider bar with preset key frames and functions that change how layers appear during the animation.
    • Another invaluable use for Photoshop CS3 users is its 3D function. Graphic designers can view logos with text and images as stand-alone 3D images, with fully supported and customizable characteristics.

    Create PDF, Web and Device Ready Files

    • A significant use for Photoshop CS3 is the ability to create PDF or portable document format files. Like virtual pages to the internet, PDF files are useful for viewing regardless of the viewing platform, meaning anyone on any computer can view the file. Users can create secure PDF files that require passwords to ensure only the intended audience views, downloads or prints the material within the file.
    • Photoshop CS3 features web and device ready options that enable users to customize quality and file size. Often high-quality pictures are large files, and with the web and device function, the user can view the original file in one window while previewing the same file as its size and quality is adjusted to meet file size restrictions. This feature preserves as much quality as possible.


    Introduction to Oracle Database Administration - Oracle DBA

    job describe of database administrator

    Database Administrator

    What is this job like?
    • The Internet and electronic commerce (e-commerce) generate lots of data. Computer databases that store information are found in nearly every industry. Data must be stored, organized, and managed. Database administrators work with database software to find ways to do this. They identify user needs, set up computer databases, and test systems. They ensure that systems perform as they should and add people to the system as needed. Database administrators often plan security measures. Data integrity, backup, and security are critical parts of the job.
    • Database administrators work in offices or labs. They usually work about 40 hours a week, but evening or weekend work may be needed for meeting deadlines. Telecommuting—working from home—is common for computer professionals.
    • Like other workers who spend long periods in front of a computer, database administrators can suffer eyestrain, back discomfort, and hand and wrist problems.
    How do you get ready?
    • Database administrators must be able to think logically. Being able to concentrate and pay close attention to detail is important. These computer specialists sometimes work on their own, but they often work in teams. They must be able to communicate with computer personnel, such as programmers and managers. They must also communicate with other staff who may have no computer training.
    • Rapidly changing technology requires highly skilled and educated employees. There is no single way to prepare for a job as a database administrator.
    • Employers often seek workers who have a degree in computer science, information science, or a related information technology field. 
    • Many community colleges and technical schools offer specific training programs to help meet the needs of local businesses. A growing number of businesses also seek workers with a graduate degree.
    • Despite employers' preference for those with technical degrees, persons with degrees in a variety of majors find computer jobs. One factor affecting the needs of employers is changes in technology. Employers often scramble to find workers who know the latest new technologies. Many people take courses regularly to keep up with the changes in technology.
    • Jobseekers can improve their chances by working in internship or co-op programs at their schools. There are many internships where you can learn computer skills that employers are looking for.
    • Certification is a way to show a level of competence. Many employers regard these certifications as the industry standard. One way to acquire enough knowledge to get a database administrator job is to become certified in a specific type of database management. Voluntary certification also is available through various organizations associated with computer specialists.
    • Database administrators may advance into managerial positions. For example, a promotion to chief technology officer might be made on the basis of experience managing data and enforcing security.


    How much does this job pay?

    • In May 2008, average yearly wages of database administrators were $72,900. Database administrators who worked at companies that designed computer systems earned an average of $81,050 in May 2008.
    How many jobs are there?

    • There were about 120,400 database administrators in 2008.



    My survey

    My Dear fRIEND,
    pLEASE hELP me Done The survey...
    thx thx....

    Thursday 22 December 2011

    My Group

    Group discussion...
    haven done my database project...how a?i really dun know....haiz....so sad la....
    hope today can fast fast finish and will left one thing......
    god bless me la.....














    Tuesday 13 December 2011

    Benefit of Database

    What is database?haha.....anybody know?hahaha.....let me explain....
    Database is a collection of data which has been organised so that a computer program can quickly select desired items.
    Do u know the benefits using a database,the benefits of database is:

    Fast Queries

    Searching for information or relationships within a large amount of data is typically much faster using a database vs. Excel or some other spreadsheet software.
    Multiple Users

    A database can be accessed by multiple users at the same time. This is especially beneficial for large businesses with many employees who need access to the same data at the same time.
    Portability

    A database, with the proper settings, can be accessed from anywhere in the world through the Internet, allowing traveling employees to access needed data away from the office.
    Flexibility

    Using different views--which are custom data representations--each user has the ability to see the data in a way that benefits them the most. Additionally, the data can be referenced by many different applications.
    Longevity

    Data stored in an electronic database can be used in newer Database Management System (DBMS) software as it is released. With very few exceptions, all new DBMS software will work on existing databases