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Kyoto Cabinet
Tkrzw is a library of routines for managing key-value databases. Tokyo Cabinet was sponsored by the Japanese social networking site Mixi, and was a multithreaded embedded database manager and was announced by its authors as "a modern implementation of DBM". Kyoto Cabinet is the designated successor of Tokyo Cabinet, while Tkrzw is a recommended successor of Kyoto Cabinet. Tokyo Cabinet features on-disk B+ trees and hash tables for key-value storage, with "some" support for transactions. See also * Berkeley DB * LevelDB LevelDB is an open-source on-disk key-value store written by Google fellows Jeffrey Dean and Sanjay Ghemawat. Inspired by Bigtable, LevelDB is hosted on GitHub under the New BSD License and has been ported to a variety of Unix-based systems, mac ... References External links * {{official website Kyoto Cabinet official website*Kyoto Cabinet (Website Carnegie Mellon Database Group)Tokyo Cabinet official website*Tokyo Cabinet (Website Carnegie Mellon Databa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Google
Google LLC () is an American multinational technology company focusing on search engine technology, online advertising, cloud computing, computer software, quantum computing, e-commerce, artificial intelligence, and consumer electronics. It has been referred to as "the most powerful company in the world" and one of the world's most valuable brands due to its market dominance, data collection, and technological advantages in the area of artificial intelligence. Its parent company Alphabet is considered one of the Big Five American information technology companies, alongside Amazon, Apple, Meta, and Microsoft. Google was founded on September 4, 1998, by Larry Page and Sergey Brin while they were PhD students at Stanford University in California. Together they own about 14% of its publicly listed shares and control 56% of its stockholder voting power through super-voting stock. The company went public via an initial public offering (IPO) in 2004. In 2015, Google was reor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DBM (computing)
In computing, a DBM is a library and file format providing fast, single-keyed access to data. A key-value database from the original Unix, ''dbm'' is an early example of a NoSQL system. History The original ''dbm'' library and file format was a simple database engine, originally written by Ken Thompson and released by AT&T in 1979. The name is a three letter acronym for ''DataBase Manager'', and can also refer to the family of database engines with APIs and features derived from the original ''dbm''. The ''dbm'' library stores arbitrary data by use of a single key (a primary key) in fixed-size buckets and uses hashing techniques to enable fast retrieval of the data by key. The hashing scheme used is a form of extendible hashing, so that the hashing scheme expands as new buckets are added to the database, meaning that, when nearly empty, the database starts with one bucket, which is then split when it becomes full. The two resulting child buckets will themselves split when the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Database Engines
In computing, a database is an organized collection of data stored and accessed electronically. Small databases can be stored on a file system, while large databases are hosted on computer clusters or cloud storage. The design of databases spans formal techniques and practical considerations, including data modeling, efficient data representation and storage, query languages, security and privacy of sensitive data, and distributed computing issues, including supporting concurrent access and fault tolerance. A database management system (DBMS) is the software that interacts with end users, applications, and the database itself to capture and analyze the data. The DBMS software additionally encompasses the core facilities provided to administer the database. The sum total of the database, the DBMS and the associated applications can be referred to as a database system. Often the term "database" is also used loosely to refer to any of the DBMS, the database system or an application ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Free Software Programmed In C++
Free may refer to: Concept * Freedom, having the ability to do something, without having to obey anyone/anything * Freethought, a position that beliefs should be formed only on the basis of logic, reason, and empiricism * Emancipate, to procure political rights, as for a disenfranchised group * Free will, control exercised by rational agents over their actions and decisions * Free of charge, also known as gratis. See Gratis vs libre. Computing * Free (programming), a function that releases dynamically allocated memory for reuse * Free format, a file format which can be used without restrictions * Free software, software usable and distributable with few restrictions and no payment * Freeware, a broader class of software available at no cost Mathematics * Free object ** Free abelian group ** Free algebra ** Free group ** Free module ** Free semigroup * Free variable People * Free (surname) * Free (rapper) (born 1968), or Free Marie, American rapper and media personal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
C++ Libraries
C++ (pronounced "C plus plus") is a high-level general-purpose programming language created by Danish computer scientist Bjarne Stroustrup as an extension of the C programming language, or "C with Classes". The language has expanded significantly over time, and modern C++ now has object-oriented, generic, and functional features in addition to facilities for low-level memory manipulation. It is almost always implemented as a compiled language, and many vendors provide C++ compilers, including the Free Software Foundation, LLVM, Microsoft, Intel, Embarcadero, Oracle, and IBM, so it is available on many platforms. C++ was designed with systems programming and embedded, resource-constrained software and large systems in mind, with performance, efficiency, and flexibility of use as its design highlights. C++ has also been found useful in many other contexts, with key strengths being software infrastructure and resource-constrained applications, including desktop applicatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LevelDB
LevelDB is an open-source on-disk key-value store written by Google fellows Jeffrey Dean and Sanjay Ghemawat. Inspired by Bigtable, LevelDB is hosted on GitHub under the New BSD License and has been ported to a variety of Unix-based systems, macOS, Windows, and Android. Features LevelDB stores keys and values in arbitrary byte arrays, and data is sorted by key. It supports batching writes, forward and backward iteration, and compression of the data via Google's Snappy compression library. LevelDB is not an SQL database. Like other NoSQL and dbm stores, it does not have a relational data model and it does not support SQL queries. Also, it has no support for indexes. Applications use LevelDB as a library, as it does not provide a server or command-line interface. MariaDB 10.0 comes with a storage engine which allows users to query LevelDB tables from MariaDB. History LevelDB is based on concepts from Google's Bigtable database system. The table implementation for the Bigtable ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Berkeley DB
Berkeley DB (BDB) is an unmaintained embedded database software library for key/value data, historically significant in open source software. Berkeley DB is written in C with API bindings for many other programming languages. BDB stores arbitrary key/data pairs as byte arrays, and supports multiple data items for a single key. Berkeley DB is not a relational database, although it has advanced database features including database transactions, multiversion concurrency control and write-ahead logging. BDB runs on a wide variety of operating systems including most Unix-like and Windows systems, and real-time operating systems. BDB was commercially supported and developed by Sleepycat Software from 1996 to 2006. Sleepycat Software was acquired by Oracle Corporation in February 2006, who continued to develop and sell the C Berkeley DB library. In 2013 Oracle re-licensed BDB under the AGPL license. As of 2022 Oracle has ceased to develop BDB. Bloomberg LP continues to develop a f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transaction (database)
A database transaction symbolizes a unit of work, performed within a database management system (or similar system) against a database, that is treated in a coherent and reliable way independent of other transactions. A transaction generally represents any change in a database. Transactions in a database environment have two main purposes: # To provide reliable units of work that allow correct recovery from failures and keep a database consistent even in cases of system failure. For example: when execution prematurely and unexpectedly stops (completely or partially) in which case many operations upon a database remain uncompleted, with unclear status. # To provide isolation between programs accessing a database concurrently. If this isolation is not provided, the programs' outcomes are possibly erroneous. In a database management system, a transaction is a single unit of logic or work, sometimes made up of multiple operations. Any logical calculation done in a consistent mode in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hash Table
In computing, a hash table, also known as hash map, is a data structure that implements an associative array or dictionary. It is an abstract data type that maps keys to values. A hash table uses a hash function to compute an ''index'', also called a ''hash code'', into an array of ''buckets'' or ''slots'', from which the desired value can be found. During lookup, the key is hashed and the resulting hash indicates where the corresponding value is stored. Ideally, the hash function will assign each key to a unique bucket, but most hash table designs employ an imperfect hash function, which might cause hash ''collisions'' where the hash function generates the same index for more than one key. Such collisions are typically accommodated in some way. In a well-dimensioned hash table, the average time complexity for each lookup is independent of the number of elements stored in the table. Many hash table designs also allow arbitrary insertions and deletions of key–value pairs, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
B+ Tree
A B+ tree is an m-ary tree with a variable but often large number of children per node. A B+ tree consists of a root, internal nodes and leaves. The root may be either a leaf or a node with two or more children. A B+ tree can be viewed as a B-tree in which each node contains only keys (not key–value pairs), and to which an additional level is added at the bottom with linked leaves. The primary value of a B+ tree is in storing data for efficient retrieval in a block-oriented storage context — in particular, filesystems. This is primarily because unlike binary search trees, B+ trees have very high fanout (number of pointers to child nodes in a node, typically on the order of 100 or more), which reduces the number of I/O operations required to find an element in the tree. History There is no single paper introducing the B+ tree concept. Instead, the notion of maintaining all data in leaf nodes is repeatedly brought up as an interesting variant. Douglas Comer notes in an ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embedded Database
An embedded database system is a database management system (DBMS) which is tightly integrated with an application software; it is embedded in the application. It is a broad technology category that includes: * database systems with differing application programming interfaces ( SQL as well as proprietary, native APIs) * database architectures ( client-server and in-process) * storage modes (on-disk, in-memory, and combined) * database models ( relational, object-oriented, entity–attribute–value model, network/CODASYL) * target markets The term ''embedded database'' can be confusing because only a small subset of embedded database products are used in real-time embedded systems such as telecommunications switches and consumer electronics. (See mobile database for small-footprint databases that could be used on embedded devices.) Implementations Major embedded database products include, in alphabetical order: * Advantage Database Server from Sybase Inc. * Berkeley DB from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Database Engine
A database engine (or storage engine) is the underlying software component that a database management system (DBMS) uses to create, read, update and delete (CRUD) data from a database. Most database management systems include their own application programming interface (API) that allows the user to interact with their underlying engine without going through the user interface of the DBMS. The term "database engine" is frequently used interchangeably with "database server" or "database management system". A "database instance" refers to the processes and memory structures of the running database engine. Storage engines Many of the modern DBMS support multiple storage engines within the same database. For example, MySQL supports InnoDB as well as MyISAM. Some storage engines are transactional. Additional engine types include: *Embedded database engines *In-memory database engines Design considerations Information in a database is stored as bits laid out as data structures in s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
