Friday 30 December, 2011

VII. Database


VII. Database

Paragraph Answers
1.What are the Disadvantages of Manual Data Processing
  • The efficiency and correctness of data processing are limited.
  • Manual methods take more time.
  • In general human beings are liable to make computational and parallax errors.
  • Manual data processing involves use of papers at each stage. It is difficult and unmanageable.
  • Implementation of corrections, changes and modifications are difficult in manual data processing.
2.What are the Advantages of Computerised Data Processing
  • Manpower is considerable saved.
  • The processing speed is fast.
  • The chances of errors are less in computerized data processing.
  • Can be store large amount of the data and information in the computer storage medium.
  • Can be share data and resources from one computer system to the other at a very fast speed and with very little effort
  • It is easy to edit the data including correction, changes and modifications.
  • Computerized database is highly effective for searching, sorting and merging files,
3.How will we manipulate the database?
  • Searching
  • Sorting
  • Merging
  • Performing Calculations on data
  • Filtering
  • Editing the database
  • Report Generation
Searching
  • Searching is a process to select a desired specific data from a database.
  • Searching is done using database commands on the relevant fields.
  • Ex. To select the student ranking first in a class
Sorting
  • Sorting is the process of arranging the data in a table in some order.
  • We can sort the records in ascending or descending orders based on any field in the table.
  • Ex. To sort the students in the ascending or descending order of their total marks
Merging
  • Merging is a process of joining data from two or more tables of the same or different databases.
Performing Calculations on data
  • We can do any kind of arithmetic calculations on the data stored in the database
Filter
  • A filter is also a type of query.
  • It is also used to select and display records, which match a certain condition.
  • The remaining records are hidden form the user
  • StarOffice Base allows you to use two types of filters. They are Auto Filter and Standard Filter
Editing the Database
  • Editing is a process of performing corrections on the existing data, deleting the existing data, field(s), or record(s), adding new data, field(s), record(s) or changing the format of the database
Report Generation
  • A report is printed information based on a query that gathers criteria-matching data and, in some cases, performs mathematical calculations
  • We may generate any desired report, from the data of the database.
4.Explain the classification of database.
Based on the conceptual structures, the databases can be classified as follows:
  • Flat – File database
  • Relational database
  • Hierarchical database
  • Network database
  • Object-Oriented database
Flat – File Database
  • A database file that consists of a single data table is a Flat-file database.
  • It can be quite useful for certain single user or small-group situations, especially for maintaining lists such as address lists or inventories.
  • They do not allow for more complex requests
  • Multiple data tables are not possible in flat-file database
Relational database
  • A relational database made up of a set of related table.
  • In a relational database, one or more common fields existing in two or more tables create a relationship between these tables.
  • The common field or fields are called the Keys.
A primary key is a key that uniquely identifies a record in a database table.
Hierarchical database
  • The hierarchical database structures were primarily used on Main Frame computers.
  • In hierarchical databases, records are organized in a tree like structure by type.
  • The relationship between record types is said to be a parent-child relationship, in which any child type relates only to a single parent type
Network database
  • The Network database is very similar to the hierarchical structure except that any one record type can relate to any number of other record types.




Object Oriented database
  • An object is defined by its characteristics, attributes and procedures.
  • Characteristics can be text, sound, graphics, and video.
  • Attributes might be colour, size, style, quantity, and price.
  • A procedure refers to the processing or handling that can be associated to the object.
5.What is Basis Concepts of Database Management Systems (DBMS)
  • A DMBS is a program, or collection of programs.
  • It allows any number of users to access data, modify it ,and construct simple and complex requests to obtain and work with selected records.
  • DBMS is used to provide extremely quick access and retrieval from large databases.
  • DBMS tasks fall into three general categories.
  1. Entering data into the database.
  2. Reordering records in the database.
  3. Obtaining subsets of the data.

6.How to create database ?
In StarOffice window
click on File →New→Database.
The Database Wizard dialog box appears
  • Select the ‘Create a new Database’ option for creating a new
  • database or
  • select the ‘Open an existing database file’ option for opening an existing database.
Click Finish
The Save As dialogue box appears prompting you to save the
database created.
Type the database file name in the File name text box.
Click on Save
7.Explain the method of creating a table.
To create a new table,
  • Click on the Table icon in the <Database> pane and
  • Click on the ‘Create Table in Design view’ in the Tasks pane or
  • Select Insert ->Table Design menu
A Table Design window appears
In Table Design window,
  • Enter the field name.
  • Press the Tab key to move to the next column,
  • The Field Type. StarOffice Base displays a drop-down list box with the different field types.
  • Select the type you want by clicking on it.
  • In the lower part of the window, the Field Properties pane is displayed.
  • This pane allows you to further customize the field
To assign a primary key
Right Click on the small triangle to the left of the field
A shortcut menu appears.
Click on Primary key.
A small yellow key appears to the left of the field to mark it as the primary key
To Save the Table
Press Ctrl + S keys or go to the File - Save
Enter the name of the table in the dialog box and click on Save
8.How to edit the Data in Base?
  • Editing may include changing a value of a field in a record,
  • deleting a record or appending a record.
  • And also to change the font type, size and the height of the rows.
To edit a record,
  • First select the record by clicking on the record pointer.
  • Right click on the record pointer of the selected record
A shortcut menu appears, select the following
1.Delete Rows - To delete the selected record
2.Row Height - To Specify the row height
Now, Row height dialogue box appear.
Enter the value and click on OK button
3.Table Format, - Tableformat dialog box appears
Using this dialog box, the font type, style, size, colour can be changed
To append a record,
Enter the new record at the end of the table.
Save
Press Ctrl + S keys or click on the Save icon
9.How will you sort the records?
Sorting is the process of arranging the data in a table in some order.
We can sort the records in ascending or descending orders based on any field in the table
To sort a Table,
1. Open the table that you want to sort.
2. Select the field you want to sort by clicking on the field name at the top of the table.
3.Then click on the Sort Ascending icon or Sort Descending icon
Multiple Sorting:
Multiple sorting means sorting on more than one field of a table at the same time
Click on the Sort icon .
The sort order dialog box appears
Select the fields from Field name drop-down list boxes.
For each field specify the order
Click OK.
The records will be displayed in the sorted order.
Delete sort
To display the records in the original order, click on the Remove
Filter/Sort icon .
10.Explain the procedure to create Query in Database.
  • Queries are special views of the data in a table
  • Queries are user-constructed statements that set conditions for selecting and manipulating data in one or more tables
  • and assembling the criteria-matching data into information
  • The output from a query does not affect the original table.
  • The result from a query is always stored separately and can be viewed at any time
To create a query in StarOffice Base,
Right click on Queries in the <Database> pane.
On the Tasks pane , Select ‘Use wizard to Create Query’,
1.The Query wizard-Field selection appears
From the Tables combo box, Select the table
The list of fields in the selected table are appears in the Available fields text area.
To select all the fields at the same time then click on the >> button.
To select on field at a time then click on the > button
Click on Next
2.The Query wizard-Sorting order appears
This window allows you to sort of four fields
If it is not necessary to specify a sort order
Click on Next
3.The Query wizard-Search condition appears
  • To satisfy all the search then select ‘Match all of the following’
  • Select the field in Fields combo box, then select condition in the Condition box and then type value in the Value box.
  • Click on Next
4.The Query wizard - Detail or Summary appears
  • This specifies whether to display all records of the query, or only the results of aggregate functions
  • Click on Next
5.The Query wizard- Aliases appears
  • This window allows you to provide the alias names for the fields
  • Click on Next
6.The Query wizard- Overview appears
This window allows you to specify a name for the query.
  • The Display Query radio button - To execute the query immediately
  • The Modify Query option -To modify the query
  • Click on Finish button
In Queries pane , Double click Query icon to open the query table
11.Explain Filters with an example.
  • A filter is also a type of query.
  • It is also used to select and display records, which match a certain condition.
  • The remaining records are hidden form the user.
  • Filter affects the original table
  • Filter cannot be stored
  • Two types of filters are Auto Filter and Standard Filter
Auto Filter
Used to display only the records, which match the value of the current field.
Standard Filter
Filter used with a condition called Standard Filter or Default Filter.
Used to specify the condition by Filter Window
Example
Open an existing query
Click the Standard Filter icon from the main toolbar.
A Filter window will appear.
Select Maths in the Field name box.
Select > operator in the Condition box.
Type 90 in the Value box.
Click on OK.
12.Explain the procedure to be followed to design a form in staroffice base.
  • Forms are user defined screens that are used to make it easier
to enter, view and edit the data in a table or a query.
1.To design a form in Star Base
Select Form icon from the <Database> pane
Select ‘Use Wizard to Create Form’.
2.Form Wizard – Field Selection appears
  • Select the table or query from Tables combo box.
  • Select fields from the ‘Available fields’ text area by using > or >> button
  • Click on Next
3.Form Wizard – Set up a subform appears
  • If you insert another form click on ‘Add Subform’ check box otherwise Click on Next
4.Form Wizard – Arrange controls appears
  • Choose a style for displaying the fields in the form
  • Click on Next
5.Form Wizard – Set Data entry appears
  • Select the data entry mode
  • Click on Next
6.Form Wizard – Apply styles appears
  • Select any one Apply style
  • Select field border style
  • Click on Next
7.Form Wizard – Set name appears
  • Type the name of the form
  • To enter the data and display the data ,select ‘Work with the form’
  • To modify ,select ‘ Modify the form
  • Click on Finish button


13.How to generate a report in staroffice base?
  • A report is printed information that is assembled by gathering data based on user supplied criteria
To create a report in StarOffice Base
Right click on Reports in the <Database> pane.
Click ‘Use Wizard to Create Report’.
1.Report wizard - Field Selection appears
  • Select the table or query from Tables combo box.
  • Select fields from the ‘Available fields’ text area by using > or >> button
  • Click on Next
1.Report wizard – Labeling Fields appears
  • Here you can modify the labels
  • Click on Next
2.Report wizard – Grouping appears
  • Here records can be grouped together
  • Click on Next
3.Report wizard – sort options appears
  • Here the sort criteria can be specified
  • Click on Next
4.Report wizard – Choose layout appears
  • Here you can customize the report by selecting the Layout of Data, Layout of Headers and Footers and Orientation
  • Click on Next
5.Report wizard – create report appears
  • Enter the Title of Report
  • Choose Static or Dynamic report
  • Select create report now or Modify report layout radio button
  • Click on Finish button
To view the report
Click on the Reports in the Database Pane and
Double click on the Report Name in the Reports pane





14. How will you insert a Calc cell range into a text document?
Open a StarOffice Calc (spreadsheet) that contains the data.
  • Select the cell range
  • Choose Edit ->Copy.
Open a StarOffice Writer (text) document
  • Choose Edit-> Paste special.
  • In the Paste Special dialog, select DDE link, and then click OK.
The copied cell range will now be displayed in the text document
15. How to insert a text outline into a presentation?
  • In the text document that contains the outline,
Choose File->Send -> Outline to presentation
A new presentation document is created which has the outline
Applied
  • If you want to transfer each heading together
Choose File -> Send -> AutoAbstract to Presentation command.
16.How to copy data by Drag and Drop method ?
Open StarOffice Impress presentation
Open the Calc spreadsheet
In the spreadsheet, select the cell range.
Just drag-and-drop the selected range into the presentation (use Alt + Tab )
To Edit
Double-click the cell.
The Calc menus and toolbars are displayed
To exit the edit mode, click outside the plug-in.
17.How to inserting a Database table into a Text document
Open StarOffice Base,
Select the table which contains data.
Choose Edit -> Copy or press Ctrl + C .
Open StarOffice Writer, select Edit -> Paste.
Insert Database Column dialog box appears
  • Select whether the data should be inserted as a table, as fields or as text.
  • To format the table ,click on AutoFormat and select any one format template.
  • Move the listed database fields into the table column(s) list box using > or >> or double click an entry.
In Insert table heading,
Apply column name
Uses the field names of the database table as headings
Create row only
Inserts an empty heading line into the text table.
You can define headings in the document.
  • Click Ok to view the inserted table in the text document

Short Answer
1. What is a data?
  • Data is a fact about a people, place or an entity
  • Data is input to the computer
  • Ex. Name = vijay , age = 16 , Vijay & 16 – Data
2.What is an information?
  • Information is defined as a set of processed data that convey the relationship between data considered.
  • It is a group of related data conveying some meaning
  • Information is output
  • Ex. Vijay is 16 years old
3. What are the various data types in S.O.Calc?
The various Data types are: 1. Character 2. Number or 3. Boolean.
4.What is Database?
  • A database is a repository of collections of related data or facts.
  • Thus, a Database is a collection of data organized in a structure which is logical and easy to understand and manipulate.
5. What is meant by processing?
  • Processing means to do some operations or computations on the data of different variables to relate them and convey some meaning.
6. What are the two types of Data processing?
1. Manual Data Processing and
2. Computerised Data Processing.
7. What are the various types of manipulation possible in manipulating a database?
1. Searching, 2. Sorting, 3. Merging, 4. Filtering, 5. Performing Calculations on data, 6.Editing the database, 7.Report Generation.
8. What is meant by Searching?
  • Searching is a process to select a desired specific data from a database.
  • Searching is done using database commands on the relevant fields.
  • Ex. To select the student ranking first in a class
9. What is meant by Sorting
  • Sorting is the process of arranging the data in a table in some order.
  • We can sort the records in ascending or descending orders based on any field in the table.
  • Ex. To sort the students name in the ascending
10. What is meant by Merging?
  • Merging is a process of joining data from two or more tables of the same or different databases.
12. What is meant by Editing the database?
  • Editing is a process of performing corrections on the existing data, deleting the existing data, field(s), or record(s), adding new data, field(s), record(s) or changing the format of the database




13.Mention the steps imposed in data processing?
The steps involved in data processing are;
1. Data collection,
2.Verification and Validation of data
3. Report Generation
14. On the basis of the conceptual structure how can the databases be classified.
Based on the conceptual structures, the data bases can be classified as follows:
1. Flat-File database 2. Relational database 3. Hierarchical database 4. Network database 5. Object Oriented database
15. What is a Flat-File database? Ref. Detail 4
16. Write a note on reports in StarOffice Base? Or What is a Report?
A report is printed information based on a query that gathers criteria-matching data and, in some cases, performs mathematical calculations
17. How will you save the table after creating its structure?
To save the table,
Press Ctrl + S or Click on File -> Save
Enter the name of the table in the dialog box which appears
Click on Save.
20. What is meant by multiple sorting?
Multiple Sorting:
Multiple sorting means sorting on more than one field of a table at the same time
Click on the Sort icon .
The sort order dialog box appears
Select the fields from Field name drop-down list boxes.
For each field specify the order
Click OK.
The records will be displayed in the sorted order.
21. What are forms?
Forms are user defined screens that are used to make it easier
to enter, view and edit the data in a table or a query.
22. What is SQL?
  • Every DBMS supports a language that is similar to a programming language.
  • This language is called the Structured Query Language (SQL),
  • It is designed specifically for communicating with a database using statements
23.What are the uses of query languages (SQL)?
We can do the following using a query language:
  • Search the database to locate records
  • Establish relationships or links between tables to update records.
  • List a subset of records.
  • Perform calculations.
  • Delete obsolete records
  • Perform other data management tasks
24. What is the use of flat-file database? Ref. Detail 4
25. What is a Relational data base? Ref. Detail 4
27. What are the tasks in DBMS?
DBMS fall into one three general categories:
1.Entering data into the database, 2. Recording records in the database and 3. Obtaining Subsets of the data.
28. What is a Primary key?
  • The Primary Key is a field in a table that uniquely identifies every record in the table.
  • The primary key becomes very important when there are multiple tables, with common fields.
  • Every table in StarOffice Base must have a primary key.
29.How to assign a primary Key in a table?
To assign a primary key
  • Right Click on the small triangle to the left of the field
  • A shortcut menu appears.
  • Click on Primary key.
  • A small yellow key appears to the left of the field to mark it as the primary key.
30. What is the Database Management System (DBMS)?
  • A Database Management System (DBMS) is a program, or collection of programs.
  • It allows any number of users ,
  • to access data, modify and construct simple and complex requests to obtain and work with selected records.
31. List and define the three components that make up a database.
1. The entire collection or related data in one table is referred to as a File or a Table.
2. Each row in a table represents a Record which is a set of data for each database entry.
3. Each column in a table represents a Field,
What primary characteristics distinguish a Flat-File database from a Relational database? Ref. Detail 4
Which database structure is characterised by parent-child relationship among record types? Ref. Detail 4
List and describe the elements that makeup an object in the Object Oriented database model. Ref. Detail 4
List the various field types that can exist in a database
StarOffice Base allows twenty different field types as given below:
1. Text [VARCHAR] 2. Text [VARCHAR_IGNORECASE]
3. Text (fix) 4. Number
5. Date / Time 6. Date
7. Time 8. Yes / No
9. Memo 10.Image
11. Decimal 12. Binary Field (Fixed)
13. Binary field 14. Integer
15.Tiny Integer 16. small Integer
17. Big Int 18. Float 19.Real 20.Double
32.. What does it mean to 'filter' database records? Or What is meant by Filtering?
  • A filter is also a type of query.
  • It is also used to select and display records, which match a certain condition.
  • The remaining records are hidden form the user.
  • Filter affects the original table
  • Filter cannot be stored
  • Two types of filters are Auto Filter and Standard Filter
36. Describe what a query is and what it is used for?
  • Queries are special views of the data in a table
  • Queries are user-constructed statements that set conditions for selecting and manipulating data from one or more tables
  • and assembling the criteria-matching data into information
  • The output from a query does not affect the original table.
  • The result from a query is always stored separately and can be viewed at any time.
37.What are the Uses of Queries?
  • Search the database to locate records
  • Establish relationships or links between tables to update records.
  • List a subset of records.
  • Perform calculations.
  • Delete obsolete records
  • Perform other data management tasks.
38.What are the differentiate between Query and Filter?

Query
Filter
Query does not affect the original table.
Filter affects the original table
Query is always stored separately and can be viewed at any time
Filter can not be stored



No comments:

Post a Comment