Introduction Set 1 Flashcards
What is a Database?
A database is a collection of co-related information which helps in faster retrieval, insertion and deletion of data from database, and it organizes the data in form of tables, views, schemas, reports, etc.
What is DDL?
Data Definition Language. It deals with data definiton and descriptions.
What SQL statements are used in DDL?
CREATE, DROP, TRUNCATE, ALTER, COMMENT, RENAME
What is DML ?
Data Manipulation Language. It deals with data manipulation.
What SQL statements are used in DML?
SELECT, UPDATE, DELETE, INSERT, MERGE, CALL, EXPLAIN PLAN, LOCK TABLE
What is a DBMS?
It is a software used to manage a database.
Give example of DBMS
MySQL, Oracle
What tasks do DBMS perform?
Data Retrieval, Data Updation, Data Definition, User Administration
Explain Data Definiton
It helps in creation, modification and removal of definitions that define the organization of data in database.
Explain Data Updation
It helps in insertion, modification and deletion of data in database
Explain Data Retrieval
It helps in retrieval of data from the database which can be used by applications for various purposes.
Explain User Administration
It helps in registering and monitoring users, enforcing data security, monitoring performance, maintaining data integrity, dealing with concurrency control and recovering information corrupted by unexpected failure.
Disadvantages of file system or the reason why paradigm shift from filesystem to database
Redundancy of data, Inconsistency of data, Difficult data access, No backup and recovery, unauthorized access
