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Database index

Index Database index

A database index is a data structure that improves the speed of data retrieval operations on a database table at the cost of additional writes and storage space to maintain the index data structure. [1]

38 relations: B+ tree, B-tree, Big O notation, Bit array, Bitwise operation, Block (data storage), Column (database), Composite index (database), Computer file, Concurrency control, Data structure, Database, Expression (computer science), Foreign key, Full table scan, Hash table, Héctor García-Molina, Index locking, Inverted index, Jeffrey Ullman, Jennifer Widom, Linear search, Lookup table, Microsoft SQL Server, Partial index, Pointer (computer programming), Record (computer science), Relational database, Search engine indexing, Self-balancing binary search tree, SQL, Table (database), Time complexity, Tree (data structure), Unique key, User-defined function, Wildcard character, Wrox Press.

B+ tree

A B+ tree is an N-ary tree with a variable but often large number of children per node.

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In computer science, a B-tree is a self-balancing tree data structure that keeps data sorted and allows searches, sequential access, insertions, and deletions in logarithmic time.

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Big O notation

Big O notation is a mathematical notation that describes the limiting behaviour of a function when the argument tends towards a particular value or infinity.

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Bit array

A bit array (also known as bit map, bit set, bit string, or bit vector) is an array data structure that compactly stores bits.

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Bitwise operation

In digital computer programming, a bitwise operation operates on one or more bit patterns or binary numerals at the level of their individual bits.

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Block (data storage)

In computing (specifically data transmission and data storage), a block, sometimes called a physical record, is a sequence of bytes or bits, usually containing some whole number of records, having a maximum length, a block size.

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Column (database)

In a relational database, a column is a set of data values of a particular simple type, one value for each row of the database.

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Composite index (database)

A database composite index or multi-column index is an index that is based on several columns.

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Computer file

A computer file is a computer resource for recording data discretely in a computer storage device.

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Concurrency control

In information technology and computer science, especially in the fields of computer programming, operating systems, multiprocessors, and databases, concurrency control ensures that correct results for concurrent operations are generated, while getting those results as quickly as possible.

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Data structure

In computer science, a data structure is a data organization and storage format that enables efficient access and modification.

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A database is an organized collection of data, stored and accessed electronically.

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Expression (computer science)

An expression in a programming language is a combination of one or more constants, variables, operators, and functions that the programming language interprets (according to its particular rules of precedence and of association) and computes to produce ("to return", in a stateful environment) another value.

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Foreign key

In the context of relational databases, a foreign key is a field (or collection of fields) in one table that uniquely identifies a row of another table or the same table.

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Full table scan

Full Table Scan (also known as Sequential Scan) is a scan made on a database where each row of the table under scan is read in a sequential (serial) order and the columns encountered are checked for the validity of a condition.

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Hash table

In computing, a hash table (hash map) is a data structure that implements an associative array abstract data type, a structure that can map keys to values.

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Héctor García-Molina

Héctor García-Molina (born 1954) is a Mexican/American computer scientist and Professor in the Departments of Computer Science and Electrical Engineering at Stanford University.

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Index locking

In databases an index is a data structure, part of the database, used by a database system to effectively navigate access to user data.

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Inverted index

In computer science, an inverted index (also referred to as postings file or inverted file) is an index data structure storing a mapping from content, such as words or numbers, to its locations in a database file, or in a document or a set of documents (named in contrast to a forward index, which maps from documents to content).

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Jeffrey Ullman

Jeffrey David "Jeff" Ullman (born November 22, 1942) is an American computer scientist and professor at Stanford University.

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Jennifer Widom

Jennifer Widom is the Frederick Emmons Terman Dean of the Stanford School of Engineering and the Fletcher Jones Professor of Computer Science and Electrical Engineering at Stanford University.

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Linear search

In computer science, linear search or sequential search is a method for finding a target value within a list.

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Lookup table

In computer science, a lookup table is an array that replaces runtime computation with a simpler array indexing operation.

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Microsoft SQL Server

Microsoft SQL Server is a relational database management system developed by Microsoft.

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Partial index

In databases, a partial index, also known as filtered index is an index which has some condition applied to it so that it includes a subset of rows in the table.

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Pointer (computer programming)

In computer science, a pointer is a programming language object that stores the memory address of another value located in computer memory.

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Record (computer science)

In computer science, a record (also called a structure, struct, or compound data) is a basic data structure.

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Relational database

A relational database is a digital database based on the relational model of data, as proposed by E. F. Codd in 1970.

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Search engine indexing

Search engine indexing collects, parses, and stores data to facilitate fast and accurate information retrieval.

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Self-balancing binary search tree

In computer science, a self-balancing (or height-balanced) binary search tree is any node-based binary search tree that automatically keeps its height (maximal number of levels below the root) small in the face of arbitrary item insertions and deletions.

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SQL (S-Q-L, "sequel"; Structured Query Language) is a domain-specific language used in programming and designed for managing data held in a relational database management system (RDBMS), or for stream processing in a relational data stream management system (RDSMS).

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Table (database)

A table is a collection of related data held in a structured format within a database.

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Time complexity

In computer science, the time complexity is the computational complexity that describes the amount of time it takes to run an algorithm.

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Tree (data structure)

In computer science, a tree is a widely used abstract data type (ADT)—or data structure implementing this ADT—that simulates a hierarchical tree structure, with a root value and subtrees of children with a parent node, represented as a set of linked nodes.

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Unique key

In database relational modeling and implementation, a unique key (also known as a candidate key) of a relation is a minimal superkey for that relation; that is, a set of attributes such that.

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User-defined function

A user-defined function (UDF) is a function provided by the user of a program or environment, in a context where the usual assumption is that functions are built into the program or environment.

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Wildcard character

In software, a wildcard character is a kind of placeholder represented by a single character, such as an asterisk, which can be interpreted as a number of literal characters or an empty string.

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Wrox Press

Wrox Press (established in 1992) is a computer book publisher, originally based in Birmingham, England.

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Clustered index, Dense index, IDX (file format), Index (database), Index file, Key (computing), Non-clustered Index, Nonclustered index, Sparse index, Table index.


[1] https://en.wikipedia.org/wiki/Database_index

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