2. Data base management
system
A database management system is a software
package designed to define, manipulate,
retrieve and manage data in a database.
A DBMS generally manipulates the data
itself, the data format, field names, record
structure and file structure.
3. Database Vs File
System
A database is generally used for storing
related, structured data, with well define data
formats, in an efficient manner for insert,
update and or retrieval .
A file system is a more unstructured data
store for storing arbitrary, probably unrelated
data.
6. Data Definition Languages
DDL used to define database structure or
pattern.
It is used to create schema, tables, indexes,
constraints, etc. in the database.
Using the DDL statements, you can create
the skeleton of the database.
Tasks: Create, Alter, Drop,Truncate,Rename
7. Data manipulation language
Select: It is used to retrieve data from a
database.
Insert: It is used to insert data into a table.
Update: It is used to update existing data
within a table.
Delete: It is used to delete all records from a
table.
8. Data Control Languages
It is used to retrieve the stored or saved data.
The DCL execution is transactional. It also
has rollback parameters.
Grant: It is used to give user access
privileges to a database.
Revoke: It is used to take back permissions
from the user.
9. Transaction Control
Languages
TCL is used to run the changes made by the
DML statements. TCL can be grouped into a
logical transaction.
Commit: It is used to save the transaction on
the database.
Rollback: It is used to restore the database to
original since the last commit.
12. Entity Relational Model
An entity relationship model describes
interrelated tings of interest in a specific
domain of knowledge.
A basic ER model is composed of entity
types and specifies relationships that can
exist between entities.
14. Conclusion
Hybrid is good
Map Reduce takes care “rack to cluster”
Not sure how good it is for text analytical
tasks.
RDBMS often problems with data skew