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Graph databases (GDBs) have become increasingly important for managing large repositories of unstructured information, particularly due to their ability to represent complex relationships between entities. While their expressive data models and flexible query languages drive their success, the primary challenge hindering wider adoption is the efficiency of their implementation. In response to these challenges, significant research efforts, particularly in Latin America, focus on developing new data models, query languages, and efficient algorithms, including space-efficient structures like the Ring index, which supports complex queries with minimal memory footprint.

This article details the history of database management. The author, Donald Chamberlin, starts with the evolution of digital data management including Charles Bachman’s Integrated Data Store as well as the author’s own contributions to the field. Topics include E.F. Codd’s relational data model and its continued influence on the field as well as the development and current use of SEQUEL, SQL, the query language. Also discussed is the current database management movement known as NoSQL.

This article details a framework for database deficiencies utilizing possible world semantics. Topics include database rectification, database querying, intractability and tractability. The article explores possible world semantics in data exchange, inconsistent databases, probabilistic databases, tuple-independent databases, and election databases.

As data analytics has become an important application for modern data management systems, a new category of data management system has appeared recently: the scalable linear algebra system. We argue that a parallel or distributed database system is actually an excellent platform upon which to build such functionality. Most relational systems already have support for cost-based optimization--which is vital to scaling linear algebra computations--and it is well known how to make relational systems scalable. We show that by making just a few changes to a parallel/distributed relational database system, such a system can become a competitive platform for scalable linear algebra. Taken together, our results should at least raise the possibility that brand new systems designed from the ground up to support scalable linear algebra are not absolutely necessary, and that such systems could instead be built on top of existing relational technology. [ABSTRACT FROM AUTHOR]

This article presents CLOSET, a new data-driven system for the detection and reporting of conflicts of interest (COI) designed and developed at Nanyang Technological University. The article details the need for this system in research publishing, as well as its framework and capabilities, and how CLOSET is currently being used.

The article discusses the deployment of machine learning technology in production environments. The authors describe the algorithms which constitute and shape machine learning protocols with a focus on papers on subjects including the MauveDB project to integrate machine learning technology into relational databases, scalable response prediction for online advertising, and optimization of neural network queries for object detection in video streams.

The article discusses the impact of the computer programming language SQL in relation to data representations. Topics include the history of relational databases in light of SQL, the notion of transaction isolation, and the role of relational algebra in accessing databases. The use of SQL on immutable data and metadata is addressed.

The article discusses the computer science concept of eventual consistency. Alleged differences between data inside and outside relational databases are compared, the algorithmic treatment of replica data is scrutinized, and the author discusses the alleged need for trust and resolved uncertainty in managing the permissions and data access structures of application software.

The article explains the functions and operations of databases so as to aid those managing data storage in selecting the most appropriate one. It outlines the three types of data models in databases, relational, key-value, and hierarchical; different types of application programming interfaces (APIs); and the steps of a database transaction. It assesses different kinds of databases with respect to criteria including speed and data protection. Topics include the limitations of hard disks versus solid-state drives (SSDs), the benefits of SQL versus non-SQL databases, the role of page caches, and indexing.

The article presents a set of guidelines on scalable SQL and NoSQL datastores which involve relational database management systems (RDBMSs) using multiple servers. It is argued that applications must be designed for scalability in a web 2.0 context, and topics such as operations that span partitions, parallelism, and requirements for consistency guarantees are discussed. Rules are promulgated regarding issues such as high-level languages, automatic recovery, the hazards of multi-node operations, and the advantages of open source software.

The article discusses scalable SQL, focusing on the need to scale up relational database systems to internet size. Online social networks are cited as an example. Topics discussed include user load, data load, distributed processing and partitioning. The CAP (consistency, availability, partition tolerance) theory propounded by Eric Brewer is discussed, which argues that no distributed web service can guarantee all three of the CAP variables will be optimally met. The implications for scalable architecture and message delivery are analyzed in terms of global transaction models.

The article discusses structured query language (SQL), a database computer language used to manage relational database management systems, so-called noSQL databases that avoid the use of SQLs, and complexities faced by industries and practitioners in understanding and using the latter. Monopolistic aspects of the contemporary noSQL market are discussed including the concept that monopolistically competitive companies will not profit from the enterprise. Relational models, the development of SQLs by computer scientist Ted Codd, and aspects of perfect competition are discussed.

The article focuses on streaming query engine technology that processes rapidly flowing data with low latency. The author discusses why a streaming query engine is more efficient for data in flight problems than a relational database even though both have similar SQL semantics. Streaming query engines match the time-based nature of the problem, retain only the set of data necessary to solve the problem and process data asynchronously and continuously. Since they share SQL semantics, streaming query engines and relational databases can collaborate.

The article discusses the use of object-relational mapping (ORM) in dynamic languages. An ORM framework allows developers to declaratively define the mapping between the object model and database schema and express database-access operations in terms of objects. The author examines an ORM framework called GORM (Grails Object Relational Mapping) for Groovy, which allows new program elements to be created at runtime. The article compares and contrasts GORM and Hibernate, an ORM framework popular with Java developers. Also discussed are executing queries and performing basic save, load, and delete operations on persistent objects.

An interview with computer scientist Pat Selinger is presented. Topics of discussion include the data stored in relational databases, the higher-level language called SQL (Structured Query Language) used for relational systems, and the query optimization process used to get information for different records within different tables.

The article discusses relational databases, examining their usage in high technology applications in 2008 and in the future. The author indicates that SQL (Structured Query Language), a database query language, has become the most popular language for data access. Topics include the manner in which relational systems have dominated the landscape of managing data, the evolution of relational technologies, and an examination of data management needs for emerging applications. Also discussed are relational database management systems (RDBMS).

The article focuses on the need for information systems professionals to look for methodologies to develop data warehouses. The expenses incurred on data warehouses and related business intelligence technologies are likely to rise from $60 billion in 2001 to $150 billion in 2005. It is stated that the systems development life cycle (SDLC) is a general application development methodology customized to cater to the needs of a number of diverse applications, including database development. Further, the differences between the methods required to create transaction-oriented relational databases and those required to create decision-oriented dimensional data marts have been clarified.

Several projects depicting the advancement of computer-assisted reporting, particularly how journalists use relational databases and the Internet, were sponsored by the Swedish Foundation for Knowledge and Competence Development (KK Foundation). In 1996, the KK Foundation initiated INFOPAC, a communication training package offered to scientists of research projects receiving financial support. The objective of the KK Foundation was to build a critical mass within a community of researchers at a number of Swedish universities by helping them gain access to the necessary skills, contacts, and academic support to set up expert network activities in Sweden. The KK Foundation had no intention of taking on the responsibility to form a Swedish expert network. It was left up to the fellows to initiate and spearhead any permanent expert network. The fellows participated primarily as individuals, rather than representatives of their universities. Once the fellows were admitted into the program, their universities had no formal right to influence their activities. The KK Foundation allocated U.S. $250,000 for the program.

This article focuses on the topic of databases and, in particular, relational databases. There are various motives for reverse engineering of databases. One may want to migrate among database paradigms: from past hierarchical, network and relational databases to modern relational and object-oriented databases. The article adopts the object-modeling technique notation for modeling data. Data dictionary was chosen for a leading relational database management system in order to have an example with optimization by database design experts. This schema included only one simple generalization that was implemented with separate superclass and subclass tables. The discriminator was stored as an encoded enumerated type in the superclass table. In order to determine generalizations, a list was generated of possible one-to-zero-one associations through queries involving every pair of primary keys. Next foreign keys and associations were considered. Next, multiplicity by querying the data was determined. To produce a better model, several lightweight classes were added. INSET: Partial Summary of OMT Notation..

Focuses on the benefits of combined relational database management systems (DBM) and object-oriented (OO) programming language system. Description of relational DBM; Functions of object-oriented design; Definition of OO-DBM system.

This article presents information related to DATAPLEX that is a heterogeneous distributed database management system being developed by General Motors Research Laboratories. The key concept of its approach is to use the relational model as a common data model and the Structured Query Language (SQL) as a standard query language. The architecture of DATAPLEX consists of fourteen functionally-independent modules. This architecture is based on the relational model of data. Different data models used by unlike database systems structure data differently. This module identifies SQL statements in the application and records an SQL transaction in the transaction log as an attempted transaction. The SQL Parser scans and parses SQL statements to check syntactic errors. It checks whether a query references correct names of relations and attributes. It transforms a query that references global views to a query that references only stored data objects and local views. The Distributed Query Decomposer decomposes a distributed retrieval query into local queries and user location queries which merge local results.

Describes a financial application called BondDB, a relational database for a decision support system used by Wall Street investment managers. Exploitation of a relational DBMS to advantage for some data management tasks; Instance when the relational system was not helpful or could be pressed into service only by means of major or minor contortions; Identification of database constructs that would have simplified developing the application.

The article examines the QUEL language of RT-Ingres to facilitate this recursive retrieval function using the Theory of Transitive Closure. Initially, a recursive data structure is converted to a directed graph, in which a node represents a data instance and an arc represents a relationship instance. An intermediate data structure is generated to represent the tree structure that is equivalent to the directed graph. Finally, a new data structure which describes transitive closure can then be derived. Under the Relational Theory, the primary key is always unique with the foreign key capable of having multiple instances. This imposes the condition of structures using the foreign key as the transversal to be one-to-many. Consider the project management graph, where each node of the graph quantifies the duration of a task. By applying associative closure, the total duration of each leg of the graph may be calculated, and the built-in MIN function would then isolate the critical path from the resultant subgraph.

Develops an approach to relational database design that has been effective in meeting performance, integrity, understandability and extensibility. Simple tables; SQL language; Entity-relationship model; Logical Relational Design Methodology; Application of Object Modeling Technique to relational database design.

The article presents a relational model of a passive information resource dictionary system (IRDS) that is consistent with the Federal Information Processing Standard (FIPS) specifications and can be implemented and used with existing relational database management systems (RDBMS) products easily. The model intends to enhance the dictionary capabilities of existing RDBMSs while remaining easy to implement and use. It is described how the model is enhanced by adding another metalayer and the actual implementation of the enhanced model using the ORACLE RDBMS is demonstrated. The drawbacks of the model include the inability to express rules easily and the lack of time semantics for capturing the dynamic aspects of an information resource environment.

Presents the program for the normalization of relations written in Prolog language. Definition of database design; Comparison between the programs written in Prolog and programs written in conventional programming; Concept of normalization theory.

Proposes a relational database management approach for electronic data processing (EDP) auditing. Help in evaluating the adequacy of EDP control; Familiarization on the basic concepts of relational database; Application of the notion of normal forms and the relational algebra operators Project, Join and Select.

Examines a relational model of data for large shared data banks. Limitations of existing noninferential, formatted data systems; Database relations used as basis of the model; Application of certain operations on relations to the problems of redundancy and consistency in the users' model.

Examines the relational database management as a practical foundation for productivity. Growth in demands from end users for application programs; Capabilities of data processing departments; Concept of a relational processing capability.

System R, an experimental database system, was constructed to demonstrate that the usability advantages of the relational data model can be realized in a system with the complete function and high performance required for everyday production use. This paper describes the three principal phases of the System R project and discusses some of the lessons learned from System R about the design of relational systems and database systems in general. [ABSTRACT FROM AUTHOR]

By typing requests in English, casual users will be able to obtain explicit answers from a large relational database of aircraft flight and maintenance data using a system called PLANES. The design and implementation of this system is described and illustrated with detailed examples of the operation of system components and examples of overall system operation. The language processing portion of the system uses a number of augmented transition networks, each of which matches phrases with a specific meaning, along with context registers (history keepers) and concept case frames; these are used for judging meaningfulness of questions, generating dialogue for clarifying partially understood questions, and resolving ellipsis and pronoun reference problems. Other system components construct a formal query for the relational database, and optimize the order of searching relations. Methods are discussed for handling vague or complex questions and for providing browsing ability. Also included are discussions of important issues in programming natural language systems for limited domains, and the relationship of this system to others. [ABSTRACT FROM AUTHOR]

Aggregation is introduced as an abstraction which is important in conceptualizing the real world. Aggregation transforms a relationship between objects into a higher-level object. A new data type, called aggregate, is developed which, under certain criteria of "well-definedness," specifies aggregation abstractions. Relational databases defined as collections of aggregates are structured as a hierarchy of n-ary relations. To maintain well-definedness, update operations on such databases must preserve two invariants. Well-defined relations are distinct from relations in third normal form. It is shown that these notions are complementary and both are important in database design. A top-down methodology for database design is described which separates decisions concerning aggregate structure from decisions concerning key identification. It is suggested that aggregate types, and other types which support real-world abstractions without introducing implementation detail, should be incorporated into programming languages. [ABSTRACT FROM AUTHOR]

An approach for implementing a "smart" interface to support a relational view of data is proposed. The basic idea is to employ automatic programming techniques so that the interface analyzes and efficiently refines the high level query specification supplied by the user. A relational algebra interface, called SQUIRAL, which was designed using this approach, is described in detail. SQUIRAL seeks to minimize query response time and space utilization by: (1) performing global query optimization, (2) exploiting disjoint and pipelined concurrency, (3) coordinating sort orders in temporary relations, (4) employing directory analysis, and (5) maintaining locality in page references. Algorithms for implementing the operators of E. F. Codd's relational algebra are presented, and a methodology for composing them to optimize the performance of a particular user query is described. [ABSTRACT FROM AUTHOR]

This article concentrates on a specific part of the system design cycle, namely the interface between the conceptual and logical design stages for the relational model. Specifically, this article describes an expert system called FDEXPERT that derives functional dependencies from a conceptual model of the database in the form of an Entity-Relationship (ER) model. The ER model was chosen because it is one of the most well-known and frequently used models for analysis and design of the conceptual model of a database. The concept of Normal Forms has provided a sound basis for relational database design. An entity is a concrete or abstract object of an existing system. The article describes some of the automated tools used for relational database design. The logical design of the relational database is performed by accepting functional dependencies that are user-defined. Tools described in this article are, INCOD and GINCOD used for conceptual design of database applications using ER model, SECSI developed at INRIA in France supports requirements collection in natural language followed by logical and physical design of relational database applications, etc.

Highlights the Relational Data File computer system for data retrieval developed by RAND Corp. Capabilities of the system; Features of the system; Operational process of the system.

The article focuses on various issue relating to the computer industry. Virtually all commercial applications in the 1960's were based on files of fixed-length records of multiple fields, which were selected and merged. Relational databases performed a task that did not need doing for e.g., these databases were orders of magnitude slower than flat files they replaced, and they could not begin to handle requirements of real-time transaction systems. In mathematical parlance, they made trivial problems obviously trivial, but did nothing to solve the really hard data processing problems. In fact, the advent of relational databases made hard problems harder, because the application engineer now had to convince his nontechnical management that the relational database had no clothes. Most manufacturing databases of the late 1960's were of the bill of materials type, which today would be characterized as object-oriented. These databases could also respond quickly to real-time requests for information, because the data was readily accessible through pointers and hash tables-without performing joins.

The article presents abstracts of research papers related to information technology. The research paper "Transactions and Consistency in Distributed Database Systems," discusses the concepts of transaction and data consistency for distributed computing systems. The cases of partitioned data, where fragments of a file are stored at multiple nodes, and replicated data, where a file is replicated at several nodes, are discussed. It has been argued that the distribution and replication of data should be transparent to the programs which use the data. That is, the programming interface should provide location transparency, replica transparency, and failure transparency. According to the research paper "On the Correct Translation of Update Operations on Relational Views," most relational database systems provide a facility for supporting user views. Permitting this level of abstraction has the danger, however, that update requests issued by a user within the context of his view may not translate correctly into equivalent updates on the underlying database.

The author examines the benefits and process of extending SQL computer language with integer linear programming in relational databases.

An interview with computer scientist Michael Stonebraker is presented. He discusses the influence of a paper by computer scientist Ted Codd on his work on relational databases. When asked about his relationship with IBM employees working on the proprietary relational database System R, he notes that they had no formal collaboration but would occasionally exchange ideas. Other topics include query rewriting and the Ingres Corporation.

The article looks at INGRES, one of the world's first two relational databases, which was developed by computer scientists Michael Stonebraker, Eugene Wong, and Gerald Held in the 1970s. Stonebraker is the recipient of the 2014 A.M. Turing Award from the Association for Computing Machinery (ACM), and he, Held, and Wong also won the ACM's Software System Award in 1988. INGRES was written on the Unix operating system in the programming language C. Details on Stonebraker's career following the development of INGRES, including his development of the database POSTGRES and his work founding companies such as Vertica and Streambase, are also presented.

Several letters to the editor are presented in response to previously published articles including "Cybercrime: It's Serious, But Exactly How Series" by Paul Hyman from March 2013, "Positioning ACM for an Open Access Future" by Ronald F. Boisvert and Jack W. Davidson, and "Relational Model Obsolete" by Carl Hewitt from January 2013.

The article discusses the 40th birthday of the relational model of database management system (RDBMS). According to the article, International Business Machine (IBM) researcher Edgar F. Codd first wrote in this journal about how large data bank users should be protected from having to know about how the data is organized in a computer. Codd's model stored data by rows and columns that were accessed by data manipulation language. The IBM's System R project, the University of California at Berkeley's Ingres project, a paper on access path selection in RDBMS, and the Gamma Database Machine Project are discussed.

The article takes a fresh look at first normal form (1NF). A fresh look at E.F.Codd's original article on relational databases suggests a new, non-trivial definition of 1NF. Let R be a relation scheme and D the set of dependencies applicable to R, including multivalent dependencies. Y is a simple component of R if Y is a nonempty subset of the attributes of R, and there is a multivalued dependency X→→Y, where XY does not include all the attributes of R, and there is no non-empty subset Z of Y such that X→Y. The last clause is necessary to guarantee that there are at least two tuples that agree on X but do not agree on Y, thus giving Y complexity. The definition of nonsimple component seems to agree closely with Codd's intuition. The improved definition of 1NF is simple: R is in 1NF iff R has no non-simple components. If it is accepted that the problem of nonsimplicity is the problem of multivalued dependency without functional dependency, then one would conjecture that if the problem of nonsimplicity is taken care of, then the only remaining problem is that of functional dependency.

The article presents two letters to the editor, one about "Celebrating the Legacy of PLATO" by Kirk L. Kroeker, from the August 2010 issue, and the other regarding "Happy Birthday, RDBMS!” by Gary Anthes, from the May 2010 issue, together with a response by Anthes to the latter letter.

A letter to the editor is presented in response to the article “Happy Birthday, RDBMS!,” by Gary Anthes in the May 2010 issue.

This article focuses on the main topics appearing in the May 1994 issue of the periodical "Communications of the ACM." The blueprint for this issue is reverse engineering or how technology investment can grow, bend or respond to changing business requirements. It is not about buying new software components, it is about understanding existing components and remolding them to fit new demands. The writers in this issue present some valuable reverse engineering experiences in business and government applications for legacy codes, information systems, inventories, relational databases and payroll systems, among others. Also of note is Robert Arnold's "Viewpoint," tracing the early origins of software reengineering technology to present day practices and future expectations. Adaptive programming, realized by the use of propagation patterns, lifts programming to a higher level of abstraction. Adaptive object-oriented programming is introduced as an extension to conventional methods. This work is a step en route to the development of a better programming language.

The article presents the March 1, 1992 issue of the journal "Communications of the ACM." The journal draws main attention towards logic programming. The meaning of logic programming differs from person to person. For some, logic programming brings to mind particular application domains, such as expert systems, natural language processing, compiler writing, Very Large Scale Integration circuit analysis, or relational databases. To yet another group logic programming will probably signify numerous combined endeavors in logic and computer science that are producing fascinating developments in areas of massively parallel architectures, operations research, numerical analysis, and the development of large, less error-prone, software packages. The journal also covers the role of logic programming in the field of computer science. An article on implementing sets in Prolog along with its unique characteristics and special techniques has also been mentioned. The journal also contains an article that examines how programmers organize their knowledge and how program design skills are commonly taught.

Presents a letter to the editor commenting on the article "An English Language Question Answering System for a Large Relational Database," by David Waltz that was published in July 1978 issue of the periodical "Communications of the ACM."

Presents a letter to the editor commenting on the article "An English Language Question Answering System for a Large Relational Database," by David Waltz that was published in July 1978 issue of the periodical "Communications of the ACM."