Denormalization is the process of boosting up database performance and adding of redundant data which helps to get rid of complex data. Denormalization is a part of database optimization technique. This process is used to avoid the use of complex and costly joins. Denormalization doesn’t refer to the thought of not to normalize instead of that denormalization takes place after normalization. In this process, firstly the redundancy of the data will be removed using normalization process than through denormalization process…

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3NF stands for Third Normal Form. A database is called in 3NF if it satisfies the following conditions: It is in second normal form. There is no transitive functional dependency. For example: X->Z Where: X->Y Y does not -> X Y->Z so, X->Z 3NF stands for Third Normal Form, which is a normalization technique used in database design to reduce redundancy and improve data integrity. In 3NF: The table must be in 2NF (Second Normal Form). All non-prime attributes (attributes…

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What are indexes? What are B-Trees Index makes your search faster. So defining indexes to your database will make your search faster.Most of the indexing fundamentals use “B-Tree” or “Balanced-Tree” principle. It’s not a principle that is something is created by SQL Server or ORACLE but is a mathematical derived fundamental.In order that “B-tree” fundamental work properly both of the sides should be balanced. What is a Sub-Query A query nested inside a SELECT statement is known as a subquery…

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The Data model is specified as a collection of conceptual tools for describing data, data relationships, data semantics and constraints. These models are used to describe the relationship between the entities and their attributes. There is the number of data models: Hierarchical data model network model relational model Entity-Relationship model and so on. A data model is a conceptual representation of how data is structured and organized within a database system. It defines the logical structure of the data and…

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Functional Dependency is the starting point of normalization. It exists when a relation between two attributes allow you to determine the corresponding attribute’s value uniquely. The functional dependency is also known as database dependency and defines as the relationship which occurs when one attribute in a relation uniquely determines another attribute. It is written as A->B which means B is functionally dependent on A.

BCNF stands for Boyce-Codd Normal Form. It is an advanced version of 3NF, so it is also referred to as 3.5NF. BCNF is stricter than 3NF. A table complies with BCNF if it satisfies the following conditions: It is in 3NF. For every functional dependency X->Y, X should be the super key of the table. It merely means that X cannot be a non-prime attribute if Y is a prime attribute.

What is a database system? The collection of database and DBMS software together is known as a database system. Through the database system, we can perform many activities such as- The data can be stored in the database with ease, and there are no issues of data redundancy and data inconsistency. The data will be extracted from the database using DBMS software whenever required. So, the combination of database and DBMS software enables one to store, retrieve and access data…

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A Relation Schema is specified as a set of attributes. It is also known as table schema. It defines what the name of the table is. Relation schema is known as the blueprint with the help of which we can explain that how the data is organized into tables. This blueprint contains no data. A relation is specified as a set of tuples. A relation is the set of related attributes with identifying key attributes See this example: Let r…

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E-R model is a short name for the Entity-Relationship model. This model is based on the real world. It contains necessary objects (known as entities) and the relationship among these objects. Here the primary objects are the entity, attribute of that entity, relationship set, an attribute of that relationship set can be mapped in the form of E-R diagram. In E-R diagram, entities are represented by rectangles, relationships are represented by diamonds, attributes are the characteristics of entities and represented…

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ACID properties are some basic rules, which has to be satisfied by every transaction to preserve the integrity. These properties and rules are: ATOMICITY: Atomicity is more generally known as ?all or nothing rule.’ Which implies all are considered as one unit, and they either run to completion or not executed at all. CONSISTENCY: This property refers to the uniformity of the data. Consistency implies that the database is consistent before and after the transaction. ISOLATION: This property states that…

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