# Inference Rules For Functional Dependencies

Inference Rules For Functional Dependencies – Let S be the set of functional dependencies that are specified on relation schema R. Numerous other dependencies can be inferred or deduced from the functional dependencies in S. Example : Let S = {A → B, B → C} We can infer the following functional dependency from S:…

# Types of Functional Dependency with Example

 Types of Functional Dependency with Example –  Various Types of Functional Dependencies are – Single Valued Functional Dependency Fully Functional Dependency Partial Functional Dependency Transitive Functional Dependency Trivial Functional Dependency Non Trivial Functional Dependency Complete Non Trivial Functional Dependency Semi Non Trivial Functional Dependency Single Valued Functional Dependency – Database is a collection of related information…

# Functional Dependency with Examples

 Functional Dependency with Examples-  A Functional dependency is a relationship between attributes. Suppose that given the value of one attribute, we can obtain the value of another attribute. For example, if we know the value of customer account number, we can obtain customer address, balance etc. By this, we say that customer address and balance…

# Desirable Properties of Decomposition

 Desirable Properties of Decomposition – If we apply the normal forms or normalization or schema refinement technique – Decomposition to the universal table, then it may be splitted up into different fragments. At any stage, if we combine the fragments (denormalization), it should give the original table in terms of columns and rows and it…

# Lossy Join Decomposition

 Lossy Join Decomposition : The best refinement technique for the schema design is Decomposition. Decomposition refers to decompose or break-down of the relational-schema that has many attributes into several schemas with fewer attributes. We should take care some desirable properties while doing decomposition. If we do the careless decomposition, then it will lead to a…

# Process Categorisation on the basis of execution time

 The process with respect to execution time can be categorised into two types- CPU bound process– The processes which require more CPU time are called as CPU bound process. IO bound process- The process which require more IO time are called as IO bound process. These process will spend more time in wait state.   Assume…

# Normalisation or Schema Refinement or Database design

 Normalisation or Schema Refinement or Database design Normalisation or Schema Refinement is a technique of organizing the data in the database. It is a systematic approach of decomposing tables to eliminate data redundancy and undesirable characteristics like Insertion, Update and Deletion Anomalies. The Schema Refinement refers to refine the schema by using some technique. The best…

# Process State diagram

Process state diagram- Initially the process is in new state i.e the process is under creation. Once the process is created it will move to ready state. In ready state, there are multiple process, there we will select/process and schedule/dispatch it to run state. In running state, process will execute instruction. In running state, there is…

# Process management in Operating System

 Process concept- program under execution is called a process. Execution- if program is in execution- It must reside in main memory. should execute instruction on the processor. Which instruction? – process instruction   Process have various attributes, states and operations.   Process ID (PID)- It is a unique identification no. which is assigned by operating system at…

# Conversion of ER Model to Relational Model-Questions

 Conversion of ER Model to Relational Model-Questions  Question 1 : Consider the following ER Diagram –  a) How many minimum number of tables required ? Solution : Step 1 :  Conversion of Strong Entities : E1 A A1 A2 Primary Key : A E2 B B1 Primary Key : B Step 2 : Conversion of…