File Organization in DBMS | Set 3 Last Updated : 19 Sep, 2023 Comments Improve Suggest changes Like Article Like Report B+ Tree, as the name suggests, uses a tree-like structure to store records in a File. It uses the concept of Key indexing where the primary key is used to sort the records. For each primary key, an index value is generated and mapped with the record. An index of a record is the address of the record in the file. B+ Tree is very similar to a binary search tree, with the only difference being that instead of just two children, it can have more than two. All the information is stored in a leaf node and the intermediate nodes act as a pointer to the leaf nodes. The information in leaf nodes always remains a sorted sequential linked list. B+ Tree File OrganizationIn the above diagram, 56 is the root node which is also called the main node of the tree. The intermediate nodes here, just consist of the address of leaf nodes. They do not contain any actual records. Leaf nodes consist of the actual record. All leaf nodes are balanced. Advantages of B+ Tree File OrganizationTree traversal is easier and faster.Searching becomes easy as all records are stored only in leaf nodes and are sorted in sequentially linked lists.There is no restriction on B+ tree size. It may grow/shrink as the size of the data increases/decreases.Disadvantages of B+ Tree File OrganizationInefficient for static tables.Cluster File OrganizationIn Cluster file organization, two or more related tables/records are stored within the same file known as clusters. These files will have two or more tables in the same data block and the key attributes which are used to map these tables together are stored only once. Thus it lowers the cost of searching and retrieving various records in different files as they are now combined and kept in a single cluster. For example, we have two tables or relation Employee and Department. These tables are related to each other. Cluster File OrganizationTherefore this table is allowed to combine using a join operation and can be seen in a cluster file. Cluster File OrganizationIf we have to insert, update or delete any record we can directly do so. Data is sorted based on the primary key or the key with which searching is done. The cluster key is the key with which the joining of the table is performed. Types of Cluster File OrganizationThere are two ways to implement this method. Indexed Clusters: In Indexed clustering, the records are grouped based on the cluster key and stored together. The above-mentioned example of the Employee and Department relationship is an example of an Indexed Cluster where the records are based on the Department ID.Hash Clusters: This is very much similar to an indexed cluster with the only difference that instead of storing the records based on cluster key, we generate a hash key value and store the records with the same hash key value.Advantages of Cluster File OrganizationIt is basically used when multiple tables have to be joined with the same joining condition.It gives the best output when the cardinality is 1:m.Disadvantages of Cluster File OrganizationIt gives a low performance in the case of a large database.In the case of a 1:1 cardinality, it becomes ineffective.ISAM (Indexed Sequential Access Method): A combination of sequential and indexed methods. Data is stored sequentially, but an index is maintained for faster access. Think of it like having a bookmark in a book that guides you to specific pages. Advantages of ISAM :Faster retrieval compared to pure sequential methods.Suitable for applications with a mix of sequential and random access.Disadvantages of ISAM :Index maintenance can add overhead in terms of storage and update operations.Not as efficient as fully indexed methods for random access. Comment More infoAdvertise with us Next Article Introduction of DBMS (Database Management System) S Smitha Dinesh Semwal Follow Improve Article Tags : Misc DBMS GATE CS dbms Practice Tags : Misc Similar Reads DBMS Tutorial â Learn Database Management System Database Management System (DBMS) is a software used to manage data from a database. A database is a structured collection of data that is stored in an electronic device. 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It is based on first-order predicate logic and uses tuple variables to represent rows of tables.Syntax: The basi 4 min read Domain Relational Calculus in DBMSDomain Relational Calculus (DRC) is a formal query language for relational databases. It describes queries by specifying a set of conditions or formulas that the data must satisfy. These conditions are written using domain variables and predicates, and it returns a relation that satisfies the specif 4 min read Relational AlgebraIntroduction of Relational Algebra in DBMSRelational Algebra is a formal language used to query and manipulate relational databases, consisting of a set of operations like selection, projection, union, and join. It provides a mathematical framework for querying databases, ensuring efficient data retrieval and manipulation. Relational algebr 9 min read SQL Joins (Inner, Left, Right and Full Join)SQL joins are fundamental tools for combining data from multiple tables in relational databases. For example, consider two tables where one table (say Student) has student information with id as a key and other table (say Marks) has information about marks of every student id. Now to display the mar 4 min read Join operation Vs Nested query in DBMSThe concept of joins and nested queries emerged to facilitate the retrieval and management of data stored in multiple, often interrelated tables within a relational database. As databases are normalized to reduce redundancy, the meaningful information extracted often requires combining data from dif 3 min read Tuple Relational Calculus (TRC) in DBMSTuple Relational Calculus (TRC) is a non-procedural query language used to retrieve data from relational databases by describing the properties of the required data (not how to fetch it). It is based on first-order predicate logic and uses tuple variables to represent rows of tables.Syntax: The basi 4 min read Domain Relational Calculus in DBMSDomain Relational Calculus (DRC) is a formal query language for relational databases. It describes queries by specifying a set of conditions or formulas that the data must satisfy. These conditions are written using domain variables and predicates, and it returns a relation that satisfies the specif 4 min read Functional Dependencies & NormalizationAttribute Closure in DBMSFunctional dependency and attribute closure are essential for maintaining data integrity and building effective, organized and normalized databases. Attribute closure of an attribute set can be defined as set of attributes which can be functionally determined from it.How to find attribute closure of 4 min read Armstrong's Axioms in Functional Dependency in DBMSArmstrong's Axioms refer to a set of inference rules, introduced by William W. 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When working with databases, especially relational databases, it is critical to follow normalization techniques that help to eliminate 7 min read The Problem of Redundancy in DatabaseRedundancy means having multiple copies of the same data in the database. This problem arises when a database is not normalized. Suppose a table of student details attributes is: student ID, student name, college name, college rank, and course opted. Student_ID Name Contact College Course Rank 100Hi 6 min read Lossless Join and Dependency Preserving DecompositionDecomposition of a relation is done when a relation in a relational model is not in appropriate normal form. Relation R is decomposed into two or more relations if decomposition is lossless join as well as dependency preserving. Lossless Join DecompositionIf we decompose a relation R into relations 4 min read Denormalization in DatabasesDenormalization is a database optimization technique in which we add redundant data to one or more tables. 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It relies 5 min read Deadlock in DBMSA deadlock occurs in a multi-user database environment when two or more transactions block each other indefinitely by each holding a resource the other needs. This results in a cycle of dependencies (circular wait) where no transaction can proceed.For Example: Consider the image belowDeadlock in DBM 4 min read Starvation in DBMSStarvation in DBMS is a problem that happens when some processes are unable to get the resources they need because other processes keep getting priority. This can happen in situations like locking or scheduling, where some processes keep getting the resources first, leaving others waiting indefinite 8 min read Advanced DBMSIndexing in DatabasesIndexing in DBMS is used to speed up data retrieval by minimizing disk scans. Instead of searching through all rows, the DBMS uses index structures to quickly locate data using key values.When an index is created, it stores sorted key values and pointers to actual data rows. This reduces the number 6 min read Introduction of B TreeA B-Tree is a specialized m-way tree designed to optimize data access, especially on disk-based storage systems. In a B-Tree of order m, each node can have up to m children and m-1 keys, allowing it to efficiently manage large datasets.The value of m is decided based on disk block and key sizes.One 8 min read Introduction of B+ TreeA B+ Tree is an advanced data structure used in database systems and file systems to maintain sorted data for fast retrieval, especially from disk. It is an extended version of the B Tree, where all actual data is stored only in the leaf nodes, while internal nodes contain only keys for navigation.C 5 min read Bitmap Indexing in DBMSBitmap Indexing is a powerful data indexing technique used in Database Management Systems (DBMS) to speed up queries- especially those involving large datasets and columns with only a few unique values (called low-cardinality columns).In a database table, some columns only contain a few different va 3 min read Inverted IndexAn Inverted Index is a data structure used in information retrieval systems to efficiently retrieve documents or web pages containing a specific term or set of terms. In an inverted index, the index is organized by terms (words), and each term points to a list of documents or web pages that contain 7 min read SQL Queries on Clustered and Non-Clustered IndexesIndexes in SQL play a pivotal role in enhancing database performance by enabling efficient data retrieval without scanning the entire table. The two primary types of indexes Clustered Index and Non-Clustered Index serve distinct purposes in optimizing query performance. In this article, we will expl 7 min read File Organization in DBMSFile organization in DBMS refers to the method of storing data records in a file so they can be accessed efficiently. It determines how data is arranged, stored, and retrieved from physical storage.The Objective of File OrganizationIt helps in the faster selection of records i.e. it makes the proces 5 min read DBMS PracticeLast Minute Notes - DBMSDatabase Management System is an organized collection of interrelated data that helps in accessing data quickly, along with efficient insertion, and deletion of data into the DBMS. DBMS organizes data in the form of tables, schemas, records, etc. DBMS over File System (Limitations of File System)The 15+ min read Top 60 DBMS Interview Questions with Answers for 2025A Database Management System (DBMS) is the backbone of modern data storage and management. Understanding DBMS concepts is critical for anyone looking to work with databases. Whether you're preparing for your first job in database management or advancing in your career, being well-prepared for a DBMS 15+ min read Commonly asked DBMS Interview Questions | Set 2This article is an extension of Commonly asked DBMS interview questions | Set 1.Q1. There is a table where only one row is fully repeated. Write a Query to find the Repeated rowNameSectionabcCS1bcdCS2abcCS1In the above table, we can find duplicate rows using the below query.SELECT name, section FROM 5 min read Like