=> DBMS Features
------------------------------------------------------------------------
(1) . Redundancy
(2) . Security
a. Authentication
b. Authorization
(3) . Data integrity
(4) . Atomicity
=> RDBMS Features
--------------------------------------------------------------------------
1. Large amount of data can be store.
2. Structure Query language
a. DDL ( Data Definition Language)
b. DML (Data Manipulation Language)
c. DCL (Data Control Language)
d. TCL (Transaction Control Language)
e. DQL (Data Query Language)
3. multiple table can be joined.
4. Multiple relation can be created between tables relation can be
1:1 (One to one)
1:M ( One to many)
M:1 (Many to One)
M:N (It is combination of Many to one and one to many)
=> Data Models
---------------------------------------------------------------------------------
Their are several type of data model.
1. physical Data Model
2.Conceptual Data Model
3. Logical Data Model
a. Hierarchical data model
b. Network data model
c. Relational data model
d. Object data model
e. Object relational data model
=> Constraints
------------------------------------------------------------------------------------
Constraints are used to give conditions or rules on the table so that valid and meaningful data cab be store in table.
type of constraints
----------------------------------------------------
1. Unique
2. Not null
3. Primary key
a. Candidate Key
b. Secondary Key (Alternate Key)
4. Foreign key
5. Composite key
=> Normalization
----------------------------------------------------------------------------------------
Normalization means decomposing of larger and complex data into simple and smaller tables.
Advantage of normalization
--------------------------
a). Redundancy can be reduce
b). Inconsistency can be avoided.
c). Related data will be stored in table.
Their are several type of normalization.
1. First Normal Form (1st NF)
2. Second Normal Form (2nd NF)
3. Third Normal Form (3rd NF)
4. Boyce Code Normal Form (BCNF)
5. Forth Normal Form (4th NF)
=> De normalization
----------------------------------------------------------------------------------------
De normalization means it is a reverse of normalization it contains data redundancy or data repetition.
=> Database means collection of tables.
=>SQL Server contains two types of database
1) OLTP (Online Transaction Processing).
2) OLAP (Online Analytical Processing).
=> Constraints
------------------------------------------------------------------------------------
Constraints are used to give conditions or rules on the table so that valid and meaningful data cab be store in table.
type of constraints
----------------------------------------------------
1. Unique
2. Not null
3. Primary key
a. Candidate Key
b. Secondary Key (Alternate Key)
4. Foreign key
5. Composite key
=> Normalization
----------------------------------------------------------------------------------------
Normalization means decomposing of larger and complex data into simple and smaller tables.
Advantage of normalization
--------------------------
a). Redundancy can be reduce
b). Inconsistency can be avoided.
c). Related data will be stored in table.
Their are several type of normalization.
1. First Normal Form (1st NF)
2. Second Normal Form (2nd NF)
3. Third Normal Form (3rd NF)
4. Boyce Code Normal Form (BCNF)
5. Forth Normal Form (4th NF)
=> De normalization
----------------------------------------------------------------------------------------
De normalization means it is a reverse of normalization it contains data redundancy or data repetition.
=> Database means collection of tables.
=>SQL Server contains two types of database
1) OLTP (Online Transaction Processing).
2) OLAP (Online Analytical Processing).
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