Frequently Asked Questions: Database Management System

What is a Database?

A database is a collection of data for one or more uses. A database can be, as simple as, a text file with a list of names or, as complex as, a large relational database management system with in-built tools to maintain the data.

What is a Database Management System?

What is a flat-file Database?

What is a Relational Database Management System?

A relation database provide following tools to manage data in the database:

• SQL language to extract data from table(s).
• Forms to enter data into table(s).
• Report to view the results of a query.

What are the benefits of using a Relational Database?

• Potential for enforcing standards.
• Flexibility.
• Reduced application development time.
• Availability of up-to-date information to all users.
• Economies of scale.
• Data can be easily accessed.
• Data can be shared.
• Data modeling can be flexibility.
• Data storage and redundancy can be reduced.
• Data inconsistency can be avoided.
• Data Integrity can be maintained.
• Standards can be enforced.
• Security restrictions can be applied.
• Independence between physical storage and logical data design can be maintained.
• High-level data manipulation language (SQL) can be used to access and manipulate data.

How do Relational Database work?

For example, table 1 below displays 4 records and 3 fields. Each record represents the contact information of a person.
  
 

Table 1: PhoneBook

Most tables have one or group of columns that can be used to identify unique record in a table. When it a single column that can identify as a unique row, it call the primary key. For example, an Employees table might have an EmployeeID column that will contain unique row for the employee. This makes it easy to keep track of a record over time and to associate a record with records in other tables.

Foreign key column is a column in a table that is linked to primary key column(s) in another tables, thereby creating a relationship. For example, the Customer table might have a foreign key column called SalesRep that links to EmployeeID column, the primary key, in a Employee table.

What is a SQL Query?

For example, to find all the records from the phone book (table1)with last name Smith, the SQL command will be as follows:
 
     SELECT * FROM PhoneBook where LName = ‘SMITH’;

What is a Form?

What are Reports?

Does NR Computer Learning Center (NRCLC) provide training is Database Management and Database Design?

NRCLC provides hands-on classroom training, online classses and live instructor led online classes. For information on our scheduled classes, visit our website at http://www.nrclc.com/Certification/DatabaseManagement.html. For information on Corporate Training, call (714) 505-3475 or request information on Corporate Training by clicking here. NRCLC also provides online classes. Vist Online Instructor Lead Training or visit http://www.nrclc.com/Online for view list of over 100 online computer courses.

Online Database Training