What is Data?
Is raw facts
What is Information?
Is processed/structured data with a context and meaning.
What is a Database? DB
Is a shared, self-describing collection of related data + metadata.
What is Metadata?
Is data about the data. It explains the relationships and structure of the data.
What is Database Management Systems?
A software layer providing security, concurrency, backup and recovery, performance/tuning, data dictionary, and data independence.
What is Data Independence?
The ability to modify the database schema at one level without requiring changes to the schema at the next higher level.
What is Structural Independence?
Is the ability to change the physical file structure without requiring application rewrites or affecting the logical part.
What is Logical Independence?
The ability to change the conceptual schema (logical level) without affecting the external schemas (view level) or the application programs that rely on them.
What are Anomalies?
Unexpected or undesired behaviors that occur when manipulating data in a database.
Mention the types of anomalies
-Update
-Insert
-Delete
What is an update anomaly?
Update Anomaly is when a lot of the same data appears over and over again on top of the same row, and if not all the rows were updated then there is inconsistency.
What is an insert anomaly?
Insertion anomaly is when you need another record for it to be recorded, like with students you cannot register them without the student ID.
What is a delete anomaly?
Is deleting a record unintentionally by deleting a row or a table.
