Category Archives: Database Concepts

A materialized view or indexed view is a db object that stores the results of a query physically. it may be a local copy of data located remotely, or may be a subset of the rows and/or columns of a … Continue reading →

A view consists of a query accessible as a virtual table in a relational database. Unlike normal tables (base tables) in a relational database, a view is not form part of the physical schema. Changing the data in a table … Continue reading →

A lock is used when multiple users need to access a database concurrently. This prevents data from being corrupted or invalidated when multiple users try to update to the database. Any user can only modify those database records (that is, … Continue reading →

Database normalization is the process of organizing the fields and tables of a relational database to minimize redundancy and dependency. Normalization usually involves dividing large tables into smaller tables and relationships between them. The main goal is to isolate data … Continue reading →

Data modeling is a process used to define data requirements needed to support the business within the scope of corresponding information systems inside the organizations. There are three different types of data models produced while progressing from requirements to the … Continue reading →

In a relational database , a “Primary Key” is a key that uniquely defines the characteristics of each row .The primary key has to consist of characteristics that cannot be duplicated by any other row. The primary key may consist of a single … Continue reading →