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Database Management System Notes Pdf Free Download Class 10
A database is a collection of logically related information/data, which is available for one or more users organised in a way, so that it can be easily accessed, managed and updated. It is actually a place, where related piece of information is stored and various operations can be performed on it by the user.
A database is basically a computer based record/data/information keeping system. Data is raw, unorganised facts and entities relevant to the user need to be processed such as a digital representation of text, numbers, graphical images or sound. The data are stored in such a way that, they are independent of the programs used by the people for accessing the data.
e.g. Consider the names, telephone numbers and addresses of the relatives, etc. You may have recorded this data in an indexed address book or you may have stored it on a hard drive, using application software such as Microsoft Access, OpenOffice.org BASE etc.
Database can be created with the help of following structures.
Need for a Database
The need for a database arose in the early 1960s in response to the traditional file processing system. In the file processing system, the data is stored in the form of files and a number of application programs are written by programmers to add, modify, delete and retrieve data to and from appropriate files.
However, the file processing system has a number of problems, which are as follows
Some information may be duplicate in several files.
The file processing system lacks the insulation between program and data.
Handling new queries is difficult, since it requires change in the existing application programs or requires a new application program.
Unable to maintain data standards and does not provide data sharing.
In this system, all the integrity rules need to be explicitly programmed in all application programs, which are using that particular data item.
This system also lacks security features.
To overcome these problems, database system was designed.
Components of a Database
A database consists of several components. Each component plays an important role in the database system environment.
The major components of database are as follows
It is raw numbers, characters or facts represented by value. Most of the organisations generate, store and process large amount of data. The data acts as a bridge between the hardware and the software. Data may be of different types such as User data, Metadata and Application Metadata.
It is a set of programs that lies between the stored data and the users of database. It is used to control and manage the overall computerised database. It uses different types of software such as MySQL, Oracle, etc.
It is the physical aspect of computer, telecommunication and database, which consists of the secondary storage devices such as magnetic discs, optical discs, etc., on which data is stored.
It is the person, who needs information from the database to carry out its primary business responsibilities. The various types of users which can access the database system are as follows
- Database Administrator (DBA) A person, who is responsible for managing or establishing policies for the maintenance and handling the overall database management system is called DBA.
- Application Programmer A person, who writes application programs in programming languages to interact and manipulate the database are called application programmer.
- End-user A person, who interacts with the database system to perform different operations on the database like inserting, deleting, etc., through menus or forms is called end-user.
Features of a Database
Features of a database to let you manage your data are as follows:
It is the building block of any relational database model, where all the actual data is defined and entered. A database consists of many tables. Tables (relations) consist of cells at the intersection of records (rows) and fields (columns).
Different types of operations are done on the tables such as sorting, filtering, retrieving and editing of data. It is also known as a file.
- Fields or Columns (Data item) It is an area (within the record), reserved for a specific piece of data. It is the individual sub-component of one record. It contains set of characters. e.g. Customer number, customer name, street address, city, state, phone number, current address, date of birth, etc. Field in a table is also known as column or attribute.
- Records or Rows or Tuples It is the collection of data items of all the fields (information) pertaining to one entity or a complete unit of information, i.e. a person, company, transition, etc. Record of a table is also known as row, entity or tuple.
It is an inquiry into the database using the SELECT statement. These statements give you filtered data according to your conditions and specifications indicating the fields, records and summaries which a user wants to fetch from a database.
It allows you to extract information from the database based on the conditions that you define in query. MS-Access 2007 supports the database object query.
In a database, a form is a window or a screen that contains numerous fields or spaces to enter data. Forms can be used to view and edit your data. It is an interface in user specified layout.
e.g. A user can create a data entry form that looks exactly like a paper form. People generally prefer to enter data into a well-designed form, rather than a table.
When you want to print those records which are fetched from your database, design a report. It is an effective way to present data in a printed format. It allows you to represent data retrieved from one or more tables, so that it can be analysed.
The term database server may refer to both hardware and software used to run a database, according to the context. As software, a database server is the back end portion of a database application, following the traditional client server model.
Database Management System (DBMS)
It is a collection of programs that enables users to create, maintain database and control all the access to the database. It is a computer based record keeping system.
The primary goal of the DBMS is to provide an environment that is convenient and efficient for user to retrieve and store information. It acts as an interface between the application program and the data stored in the database.
DBMS is a software package that manages database. e.g. MySQL, INGRES, MS-Access, etc.
DBMS is actually a tool that is used to perform any kind of operation on data in database. It also maintains data consistency in case of multiple users. The purpose of a DBMS is to bridge the gap between information and data.
Some basic processes that are supported by a DBMS are as follows
- Specification of data types, structures and constraints to be considered in an application.
- Storing the data itself into persistent storage.
- Manipulation of the database.
- Querying the database to retrieve desired information.
- Updating the content of the database.
A short list of database applications would include:
- Inventory Payroll
- Membership Orders
- Shipping Reservation
- Invoicing Accounting
- Security Catalogues
- Mailing Medical records
Relational Database Management System (RDBMS)
RDBMS is a type of DBMS that stores data in the form of relations (tables). Relational databases are powerful, so they require few assumptions about how data is related or how it will be extracted from the databases.
An important feature of relational database system is that a single database can be spread across several tables. Base, Oracle, DB2, SAP, Sybase, ASE, Informix, Access, etc., are the examples of RDBMS.
Working of a Database
Database is created to operate large quantities of information by input, store, retrieve and manage the information. It is a centralised location which provides an easy way to access the data by several users. It does not keep the separate copies of a particular data file still a number of users can access the same data at the same time.
Working of a Database
As the diagram shows, DBMS works as an interface between the user and the centralised database. First, a request or a query is forwarded to a DBMS which works (i.e. a searching process is started on the centralised database) on the
received query with the available data and if the result is obtained, it is forwarded to the user.
If the output does not completely fulfill the requirements of the user, then a rollback (again search) is done and again search process is performed until the desired output is obtained.
Advantages of a Database/DBMS
The centralised nature of database system provides several advantages, which overcome the limitations of the conventional file processing system. These advantages are as follows
- Reduce Data Redundancy Redundancy means ‘duplication of data’. This eliminates the replication of data item in different files, extra processing required to face the data item from a large database. This also ensures data consistency and saves the storage space.
- Enforcing Data Integrity It means that, the data contained in the database is accurate and consistent. Integrity constraints or consistency rules can be applied to database, so that the correct data can be entered into the database.
- Data Sharing The data stored in the database can be shared among multiple users or application programs.
- Data Security The DBMS ensures that the access of database is done only through an authorised user.
- Ease of Application Development The application programmer needs to develop the application programs according to the user’s needs.
- Backup and Recovery The DBMS provides backup and recovery sub-system that is responsible to recover data from hardware and software failures.
- Multiple Views of Data A view may be the subset of database. Various users may have different views of the database itself.
- Enforced Standards It can ensure that, all the data follow the applicable standards.
- Data Independence System data descriptions are independent from the application programs.
Disadvantages of a Database/DBMS
There are many advantages of database, but database also have some minor disadvantages. These disadvantages are as follows
- Cost of Hardware and Software Through the use of a database system, new costs are generated due to additional hardware and software requirements.
- Complexity A database system creates additional complexity and requirements.
- Database Failures If database is corrupted due to power failure or it is corrupted on the storage media, then our valuable data may be lost or the system will stop working
- Lower Efficiency A database system is a multi-user software, which is less efficient.
|Data sharing refers to the process of sharing single piece of data among different users.|
Multiple mismatching copies of the same data is known as data inconsistency. If a field value is stored in two places in the database, then storage space is wasted and changing the data in one place will not cause data inconsistency.
Data redundancy leads to data inconsistency.
Data Integrity ensures the accuracy, reliability and consistency of the data during any operation.
Each type of data integrity are as follows
- Entity Integrity It defines the primary key of a table. Entity integrity rule on a column does not allow duplicate and null values.
- Domain Integrity It defines the type, range and format of data allowed in a column. Domain integrity states that all values in a column must be of same type.
- Referential Integrity It defines the foreign key concepts. Referential integrity ensures that data in related tables remains accurate and consistent before and after changes.
- User Defined Integrity If there is some business requirements which do not fit any above data integrity then user can create own integrity, which is called user defined integrity.
The key is defined as the column or the set of columns of the database table which is used to identify each record uniquely in a relation. If a table has id, name and address as the column names, then each one is known as the key for that table. The key field is a unique identifier for each record.
e.g. In Student table, you could use a combination of the LastName and FirstName (or perhaps LastName, FirstName to ensure you to identify each student uniquely) as a key field.
Types of Key Fields
The following are the types of key fields available in the DBMS system
A field or a set of fields that uniquely identify each record in a table is known as a primary key. Each relation has atleast one column for which each row that must have a unique value. Only one column attribute can be defined as a primary key for each table.
A primary key must possess the following properties
- It does not allow null values.
- It has a unique index.
- It allows numbers and text both.
e.g. In the student’s table, StudentId works as a primary key because it contains Ids which are unique for each student.
Note Data cannot be primary key.
The set of all attributes which can uniquely identify each tuple of a relation are known as candidate keys. Each table may have one or more candidate keys and one of them will become the primary key. The candidate key of a relation is always a minimal key. e.g. Column StudentId and the combination of FirstName and LastName work as the candidate keys for the student table.
A candidate key must possess the following properties
- For each row, the value of the key must uniquely identify that row.
- No attribute in the key can be discarded without destroying the property of unique identification.
From the set of candidate keys after selecting one of the keys as a primary key, all other remaining keys are known as alternate keys.
e.g. From the candidate keys (StudentId, combination of FirstName and LastName), if StudentId is chosen as a primary key, then the combination of FirstName and LastName columns work as alternate keys.
A field of a table (relation) that references the primary key of another table is referred to as foreign key. The relationship between two tables is established with the help of foreign key. A table may have multiple foreign keys and each foreign key can have a different referenced table. Foreign keys play an essential role in database design, when tables are broken apart, then foreign keys make it possible for them to be reconstructed.
e.g. CourseId column of student table (reference table) works as a foreign key as well as a primary key for course table (referenced table).
A data type is a data storage format that can contain a specific type or range of values. The fields within a database often require a specific type of data to be input.
e.g. A school’s record for a table student may use a character data type for the students first name and last name. The student’s date of admission and date of birth would be stored in a date format, while his or her marks in each subject may be stored as a numeric.
In MS-Access, data types can be categorised into the following types.
Field Length (Field Size)
It refers to the maximum number of characters that a field can contain. Each character requires one byte for its storage.
Field length is of two types which are as follows
- Fixed Length Field It is a type of field length in which the number of characters you enter in a field is fixed. These are present in Format option in Data Type Formatting group (in Datasheet tab) such as Currency, Euro, Per cent, etc.
- Variable Length Field In this type of field length, the number of characters is not fixed. Actually, the number of characters of the data entered in the field decide the field length.
The field length or field size of each data type are as follows
|Data Type||Field Length or Field Size||Data Type||Field Length or Field Size|
|Text||0-255 characters||Memo||0-65,536 characters|
|Number||1, 2, 4, 8 or 16 bytes||Date/Time||8 bytes|
|Currency||8 bytes||AutoNumber||4 or 16 bytes|
|Yes/No||1 bit (0 or 1)||OLE Object||Upto 2 GB|
|Hyperlink||Each part contains upto 2048 characters||Lookup Wizard…||4 bytes|
Numeric Data Types
It allows the database server to store numbers such as integers and real numbers in a column.
e.g. Age of the students, numbers obtained in subjects, etc.
|Types||Length in Bytes||Minimum Value (Signed)||Maximum Value (Signed)||Minimum Value (Unsigned)||Maximum Value (Unsigned)|
FLOAT (N, D) A small number with floating decimal point. It cannot be unsigned. Its size is 4 bytes. Here, N represents the total number of digits (including decimals) and ‘D’ represents the number of decimals.
DOUBLE (N, D) A large number with floating decimal point. It cannot be unsigned. Its size is 8 bytes.
DECIMAL (N, D) It cannot be unsigned. The maximum number of digits may be specified in the N parameter. The maximum number of digits to the right of the decimal point is specified in the D parameter.
String/Text Data Types
It allows the database server to store string values such as name of the Students, Address, etc
In a database, structure and manipulation of data are done by some commands. For this, we can use SQL commands. SQL (Structured Query Language) commands are the instructions used to communicate with the database to perform specific task that work with data.
SQL commands can be used not only for searching the database but also to perform various other functions like, create tables, add data to tables, modify data, drop the tables, set permissions for users and many more.
Data Definition Language (DDL)
DDL is used to define the structure of your tables and other objects in the database. In DBMS, it is used to specify a database schema as a set of definitions (expressed in DDL). In SQL, the Data Definition Language allows you to create, alter and destroy database objects. Basically, a data definition language is a computer language used to create and modify the structure of database objects in a database. These database objects include views, schemes, tables, indexes, etc.
This term is also known as data description language in some contexts, as it describes the fields and records in a database table.
Data definition language consists of various commands that lets you to perform some specified tasks as follows
- CREATE Uses to create objects in the database.
- ALTER Uses to alter the structure of the database table. This command can add up additional columns, drop existing columns and even change the data type of columns involved in a database table.
- DROP Uses to delete objects from the database.
- TRUNCATE Uses to remove all records from a table.
- RENAME Uses to rename an object.
Data Manipulation Language (DML)
DML provides various commands used to access and manipulate data in existing database. This manipulation involves inserting data into database tables, retrieving existing data, deleting data from existing tables and modifying existing data.
DML is mostly incorporated in SQL database. The basic goal of DML is to provide efficient human interaction with the system.
The DMLs are of two types
Procedural DMLs These require a user to specify what data is needed and how to get it.
Non-Procedural DMLs These require a user to specify what data is needed without specifying how to get it.
Various data manipulation language commands are as follows
- SELECT Used to retrieve data from a database.
- INSERT Used to insert data into a table.
- UPDATE Used to update existing data within a table.
- DELETE Used to delete all records from a table, the space of the records remains.
- LOCK TABLE Used to control concurrency.
A query language is a portion of a DML involving information retrieval only. The terms DML and query language are often used synonymously.
Differences between DDL and DML
Transaction Control Language (TCL)
TCL is playing an important role in SQL. TCL commands are used to manage transactions in database. These are also used to manage the changes made by DML statements. It allows statements to be grouped together into logical transactions. A transaction is a single unit of work.
Each individual statement is a transaction. If a transaction is successful, all of the data modifications made during the transaction is committed and became a permanent part of the database. If a transaction encounters an error and must be cancelled or rolled back, then all of the data modifications are erased. To manage all these operations, transaction control language commands are used.
Various transaction control commands are as follows
- COMMIT Used to save the work done.
- SAVEPOINT Used to identify a point in a transaction to which you can later rollback.
- ROLLBACK Used to restore database to original, since the last COMMIT.
- SET TRANSACTION It establishes properties for the current transactions.
Data Control Language (DCL)
DCL commands are used to assign security levels in database which involves multiple user setups. They are used to grant defined role and access privileges to the users.
There are two kinds of user in the schema
- Users They work with the data, but cannot change the structure of the schema. They write data manipulation language.
- Admin They can change the structure of the schema and control access to the schema objects. They write data definition language.
Basically, the DCL component of the SQL language is used to create privileges that allow to users access and manipulation of the database.
- GRANT Used to give user’s access privileges to database.
- REVOKE Used to withdraw access privileges given with the GRANT command.
Creating a Database Object
To create a new blank database, you need to perform the steps which are as follows
- Start OpenOffice Base, then getting started with its starting page will appear.
Select create a new database under what do you want to do? and click on Next button.
- Save and proceed window will appear. Click on Finish button.
- Now, SaveAs dialog box will appear where you can save your database with appropriate name. Click on Save button.
- Base creates the database with its features as Tables, Queries, Forms and Reports.
Creating Database Tables
To work with tables, click the Tables icon in the Database list. The three tasks that you can perform on a table are in the Task list
Creating Tables in Design View
Design View is a more advanced method for creating a new table. It allows you to directly enter information about each field in the table.
To create a table in design view, follow the given steps
- Open the Database.
- Select Create Table in Design View under Tasks. It will open a table as shown below
Note The field entry area is used for entering field name, field type and description. This description is optional and the field properties pane is used for entering more details for each field, i.e. field size, validation rule etc. The table needs to be opened in Design View to access the field properties.
Steps to add a new field are as follows
Step 1 Click on the first cell in the Field Name column and type the field name.
Step 2 Press Enter. The neighboring cell in the Field Type column is selected. To select the data type, click the drop-down arrow to the right of the Field Type field and select an alternative data type.
Step 3 Press Enter. A cell in the Description column will be selected. Enter a description, if required.
Step 4 Press Enter and repeat the above process for other fields.
Steps to set the field properties are as follows
Step 1 Click once on a Field Name for which you want to set the field property.
Step 2 The Field Properties will appear at the bottom of the screen as shown in the following figure.
Here, you can set the properties of related field.
Make Changes in a Design View
The Design View of a table can be modified by the following changes
Insert a Field
Steps to insert a field in a table are as follows
Step 1 Select the field, before which you want to insert a new field.
Step 2 Right click at the selected field and click at the Insert Rows option from the context menu.
Step 3 A new field is added to the table design thus, you can enter field name, data type and description.
Delete a Field
Steps to delete a field from a table are as follows
Step 1 Select the field that you want to delete.
Step 2 Right click at the selected field and choose the option Delete from context menu.
Rename a Field
You can change a field name by placing the cursor on the field, double click on it and type the new name.
Naming and Saving of a Table
Steps to save a table are as follows
Step 1 To save the table, click the Save button at the top of the screen or click the File button and select
Save. The Save As dialog box will appear as shown in following figure.
Step 2 Type the name that you want to give to your table in Table Name: text box.
Step 3 Click OK.
Entering/Removing Record into/from a Table
Once a table has been created, the field and its properties are defined, you can start to enter the records. This is done in a Datasheet View. If you create table in Design View, you need to switch to the Datasheet View to enter records.
Insert a Record
Steps to insert a record in a Datasheet View are as follows
Step 1 When you create a table, a new blank record automatically appears in the second row of the
table or If you enter data in the last record, a new blank record will automatically appear at the end of the table.
Step 2 Type data into the fields.
Step 3 When you have finished adding records in the datasheet, save it and close it.
Delete an Existing Record
Steps to delete an existing record are as follows
Step 1 Select the row which you want to delete.
Step 2 Right click on the row and select the Delete from context menu.
Using the Wizard to Create a Table
To create a table using wizard, follow the below steps
- Open the database
- Select Use Wizard to Create Table under Tasks. It will open the Table Wizard as shown below
It has four steps as
Step 1 : Select fields
You have a choice of two categories of suggested tables: Business and Personal. Each category contains its own suggested tables from which to choose. Each table has a list of available fields. We will use the DVD-Collection Sample table in the Personal category to select the fields we need.
- Category Select Personal. The Sample Tables drop down list changes to a list of personal sample tables.
- Sample Tables Select DVD-Collection. The Available fields window changes to a list of available fields for this table.
- Selected Fields Using the > button, move these fields from the Available fields window to the Selected fields window in this order: CollectionID, MovieTitle, Actor, PurchasePrice, Rating, Notes Photo and Director.
- Selected fields from another sample table. Click Business as the Category. Select Employees from the dropdown list of sample tables. Use the > button to move the Photo field from the Available fields window to the Selected fields window. It will be at the bottom of the list directly below the Director field.
If a mistake is made in the order as listed above, click on the field name that is in the wrong order to highlight it. Use the Up or Down arrow on the right side of the Selected Fields list to move the field name to the correct position. Click Next
Step 2 : Set field types and formats
In this step you give the fields their properties. When you click a field, the information on the right changes. You can then make changes to meet your needs. Click each field, one at a time and make the changes listed below.
- CollectionID Change AutoValue from No to Yes.
- MovieTitle Default
- Entry required If all of your music is in albums, change Entry required to Yes. Otherwise, leave Entry required as No.
- Length Unless you have an album title that exceeds 100 characters in length counting the spaces, do not change the length.
- Actor Use the Default setting. And since music has authors, set Entry Required to Yes.
- PurchasePrice Length: default setting. Entry required should be Yes.
- Rating Only change the Entry Required setting: from No to Yes.
- Notes No changes are required.
- Director Use the default settings.
- Photo Use the default settings. When you have finished, click Next.
- Length Unless you have an album title that exceeds 100 characters in length counting the spaces, do not change the length.
Step 3: Set primary key
- Create a primary key should be checked.
- Select option Use an existing field as a primary key.
- In the Fieldname drop down list, select CollectionID.
- Check Auto value, if it is not already checked.
- Click Next.
Step 4 : Create the table
- If desired, rename the table at this point. If you rename it, make the name meaningful to you.
- Leave the option Insert data immediately checked.
- Click Finish to complete the table wizard. Close the window created by the table wizard.
Creating a Table by Copying an Existing Table
If you have a large collection of music, you might want to create a table for each type of music you have. Rather than creating each table from the wizard, you can make a copy of the original table. Each table can be named according to the type of music contained in it. Possible names could include Classical, Pop, Country and Western, and Rock, among others.
- Click on the Tables icon in the Database pane to see the existing tables.
- Right-click on the DVD-Collection table icon. Select Copy from the context menu.
- Move the mouse pointer below this table, right-click and select Paste from the context menu. The Copy table window opens.
- Change the table name to Pop and click Next.
- Click the >> button to move all the Fields from the left window to the right window and click Next.
- Since all the Fields already have the proper File Type formatting, no changes should be needed. Click Create. The new table is created.
Opening an Existing Table
Existing table can be opened by following steps
Step 1 Find a table in the All Base Objects list (the right hand window).
Step 2 Right click on a table and select Open. This view represents the data in a table.
Renaming and Deleting a Table
Steps to rename a table are as follows
Step 1 Find a table in the All Base Objects list (the left hand window).
Step 2 Right click on a table and select Rename from context menu that appears.
Step 3 Now, type a new name for the table.
Step 4 Press Enter from the keyboard.
Steps to delete a table are as follows
Step 1 Find a table in the All Base Objects list.
Step 2 Right click on a table and select Delete.
Step 3 Now, OpenOffice Base will display the prompt
message to confirm that you want to delete the table or not.
Step 4 Click on Yes button to delete a table with its contents.
Forms are used for entering, modifying and viewing records you likely have had to fill out forms on many occasions, like when visiting a doctor’s clinic, applying for a job or registering for school. When you enter information in a form in Base, the data goes exactly where the database designer wants it to go: in one or more related tables.
There are two ways to create forms in Base
Using the Wizard to Create a Form
In the main database window, click the Form icon. Double click Use Wizard to Create Form to open the wizard. Follow the below steps to create a form using wizard,
Step 1 : Field selection
- Under Tables or queries, select DVD-Collection as the table. Available fields lists the fields for the DVD-Collection table.
- Click the right double arrow to move all of these fields to the Fields in the form list. Click Next.
Step 2: Set up a subform
Since, we have not already created a relationship between the Table1 and DVD-Collection tables. If no relationship had been defined, this would be done in step 4.
- Click the box labeled Add Subform.
- Click the radio button labeled Subform based on manual selection of fields.
- Click Next.
Step 3 : Add subform fields
This step is exactly the same as step 1. The only difference is that not all of the fields will be used in the subform.
- Select Table1 under Tables or queries.
- Use the >> button to move all the fields to the right.
- Click the ID field to highlight it.
- Use the < button to move the ID to the left.
- Click Next.
Step 4 : Get joined fields
This step is for tables or queries for which no relationship has been defined. Since we want to list all expenses by the day they occur in both the form and subform, we will join the Date fields of these two tables
- Select CollectionID from the First joined subform field dropdown list. This is not the Primary key for the Table1 table, but it is known as a Foreign key.
- Select CollectionID from the First joined main form field dropdown list. This is the Primary key for the
DVD-Collection table. Click Next.
Step 5 : Arrange controls
- Arrangement of the main form: Click Columnar – Labels on top. The labels will be placed above their field.
- Arrangement of the subform: Click As Data Sheet. (The labels are column headings and the field entries are in spreadsheet format.)
Step 6 : Set data entry
Unless you have a need for any of these entries to be checked, accept the default settings. Click Next.
Step 7 : Apply styles
- Select the color you want in the Apply Styles list.
- Select the Field border you want.
- Click Next.
Step 8: Set name
- Enter the name for the form. In this case, it is DVD.
- Click the circle in front of Modify the form if you want to modify the form otherwise select first option.
- Click Next. The form opens in Edit mode, if you select Modify the form.
2. Creating forms in Design View
To create a form using design view, follow below steps
- In the main database window, click the Form icon. Double click Create Form in Design View.
- It will open the base form where you can design your form with the help of form controls which are given in left side of form window.
Create and Manage Queries
Queries are the basis of power in a database. It is a way to get specific information from the database. They give us the ability to ask questions, record the questions for later and to take actions on the answers. There are two methods for creating a query in OpenOffice Base. These are as follows
Using the Wizard to Create a Query
In the main database window , click the Queries icon in the Databases section, then in the Tasks section, click Use Wizard to Create Query.
The Query Wizard window opens. Now follow the below steps
Step 1 : Field selection
- Select the DVD-Collection table from the dropdown list of tables.
- Select fields from the DVD-Collection table in the Available fields list.
- Click MovieTitle, and use the > button to move it to the Fields in Query list.
- Move the Actor and PurchasePrice fields in the same manner.
- Use the up arrow to change the order of the fields.
- Click Next.
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