Database Homework Help
ER Diagrams: Entity relation diagram graphically convey the relationship between different entities of a database system.It provides
information about the attributes in each entity.The main challlenge is to design a database schema for the given requirement.
The database design should meet all the user and service or business requirments and at the same time be optimized to produce fast results.
Database design: The design of a database system consist of three different types and levels of details provided by three data models - Conceptual, Logical
and Physical data model.
Conceptual Data Model is the high level design of the system that provides information about the entities within the database system and their relation with other entities. It does not provide
detailed information about all the attributes in each entity but may include some prime attributes or keys to convey the business requirments being implemented in the design.
Logical Data Model is developed from conceptual data model. It provides complete details
about different attributes included in each entity and their data types. The entities are normalized to best possible extent.The foriegn
key relationships between different attributes and other constraints are also specified.These details are hidden from the end user
but known to the database developers.
Physical Data Model as the name suggest includes the details of how the
database is stored physically by the database management system like SQL Server, MY SQL, Oracle etc. Different database management systems
have different data type, capabilities, syntax, different ways of storing table records and other differences. It needs to be supported with information
regarding use of indexes, clusters etc for performance optimization. A physical data model needs to consider the constraints of the database management system in which the database is designed.
Structured Query Languages (SQL) Programming
SQL is the common programming language used for maintaining and accessing database.Though general structure of the language is same but each
database management system provides it's own particular syntax, inbuilt functions, data types that need to be considered when using SQL programming for a particular
database system. SQL can be used for creation of database schema using Data Definition Language (DDL), manipulating data using Data Manipulation
Language (DML) and creating users /assigning roles using Data Control Language (DCL). DDL and DML is used by the database designers and developers
while DCL is usually used by database administrators.
Submit your homework now.
We can help you with different kind of assignments like