Database is the collection of data. Or the collection of data is usually referred to as the database
abstrction is the key. Doesn;t matter what field. It reduces the complexity you have to deal with. so abstract out the part when you coding is essential. Modularity is foundation of everything
A database system is a collection of interelated data and a set of programs that allow users to access and modify these data.
books has clear definition of the terms which is what i need...
how to group these attributes to form the various tables? we could employ a set of algorithms (collectively known as normalization that takes as input the set of all attributes and generates a set of tables.
user describe the kinds of operations (or transactions) that will be performed on the data. (CRUD)
in the logical-design phase, the designer maps the high-level conceptual schema onto the implementation data model of the database system that will be used.
The designer uses the resulting system-specific database schema in the subsequent physical-design phase, in which the physical features of the database are specified. These features include the form of file organization and the internal storage structures;
Database can be partitioned into several functional components
- storage manager
- query processor
- transaction management component
A transaction is a collection of operations that performs a single logical function in a database application.
![](https://img.haomeiwen.com/i6543506/b4c79b8106e91788.png)
We require that, for all relations r, the domains of all attributes of r be atomic. A domain is atomic if elements of the domain are considered to be indivisible units.
atomic means it is not divisible anymore. (I guess this is coming from atom is the smallest unit in universe)
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