The database schema is a structure of the database or it is a blueprint of the database which represents the logical configuration of all or part of a relational database. It is very difficult to change the database schema after it completed.
The database schema does not contain any data or information on it.
Types of the Database schema
There are two main types of database schema:-
1.Logical database schema:- The logical database schema defines the logical architecture of the database and it also organized the data to how to look in the form of tables.
2.Physical database schema:-Physical database schema defines how the data is stored in the storage in physical form or in the form of files, indices, etc.
What is the Database Instance?
The database schema and database instance is the two different terms that define different things in it, The database schema is the skeleton or the blueprint of the database. It was made when the database doesn’t exist.
Whereas The Database instance is the snapshot of the database, the database instance can be changed from time to time. The database schema and database instance can able to influence each other.
The DBMS system allows a database instance to interact with a database schema.
Integration requirements for database schema
There are several integration requirements of the schema. It is very helpful for us to integrate lots of data in one schema.
Minimality
Try to configure that none of the data is lost.
Overlap preservation
Every overlapping should be in the table.
Normalization
Single elements and single entities are not in the same table or group in the database schema.
Extended overlap preservation
The elements that are related to one source and are overlapped should not copy anything to the resulting database schema.
Conclusion
We think that this article is solved all your questions related to this topic, If you like to give us some suggestions so you can comment or contact us.