Special relational operations | Relational Model

SPECIAL RELATIONAL OPERATIONS These includes operations like   Selection Projection Join Division 1. Selection-To identify a set of tuples which is a part of a relation and to extract only these tuples out. The select operation selects tuples that satisfy a given predicate or condition....

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Relational Model | Relational calculas

RELATIONAL CALCULUS Relational algebra is concerned with a procedural language in which the user has to write the steps or procedure to obtain the required result.In this the user is not concerned with the detail of how to obtain information.          In relational calculus the user tell his requirement and the output is available without knowing the method about its...

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Relational Model | Integrity constraints over relation

INTEGRITY CONSTRAINTS OVER RELATION INTRODUCTION Database integrity refers to the validity and consistency of stored data. Integrity is usually expressed in terms of constraints, which are consistency rules that the database is not permitted to violate. Constraints may apply to each attribute or they may apply to relationships between tables. Integrity constraints ensure that changes (update...

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Relational Model | ER to Relational model conversion

ER TO RELATIONAL MODEL CONVERSION INTRODUCTION- In the E-R model, data is represented using entities, and relationships are defined between these entities. However, with the relational model, the entities and their relationships follow strict guidelines. Usually, an E-R model is first developed, and then it is transformed into a relational model. RULES TO CONVERT  ER TO RELATIONAL MODEL...

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Relational Model | Key constraints | Types of key

KEY CONSTRAINTS INTRODUCTION-A Key Constraint is a statement that a certain minimal subset of the fields of a relation is a unique identifier for a tuple. TYPES OF KEY CONSTRAINTS- Various types of key constraints are- Candidate key Super key Primary key Foreign key 1....

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