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SQL was initially developed at IBM by Donald D. Chamberlin and Raymond F. Boyce after learning about the relational model from Edgar F. Codd [12] in the early 1970s. [13] This version, initially called SEQUEL (Structured English Query Language), was designed to manipulate and retrieve data stored in IBM's original quasirelational database management system, System R, which a group at IBM San ...
Short title: Microsoft SQL Server/Print version - Wikibooks, open books for an open world; Author: hbossot: Image title: File change date and time: 16:12, 10 January 2016
Title Authors ----- ----- SQL Examples and Guide 4 The Joy of SQL 1 An Introduction to SQL 2 Pitfalls of SQL 1 Under the precondition that isbn is the only common column name of the two tables and that a column named title only exists in the Book table, one could re-write the query above in the following form:
Interactive Forms is a mechanism to add forms to the PDF file format. PDF currently supports two different methods for integrating data and PDF forms. Both formats today coexist in the PDF specification: [37] [52] [53] [54] AcroForms (also known as Acrobat forms), introduced in the PDF 1.2 format specification and included in all later PDF ...
A table in a SQL database schema corresponds to a predicate variable; the contents of a table to a relation; key constraints, other constraints, and SQL queries correspond to predicates. However, SQL databases deviate from the relational model in many details, and Codd fiercely argued against deviations that compromise the original principles. [3]
This is a simplified description of the most basic kind of table. Certain considerations follow from this simplified description: the term row has several common synonyms (e.g., record, k-tuple, n-tuple, vector); the term column has several common synonyms (e.g., field, parameter, property, attribute, stanchion);
Database normalization is the process of structuring a relational database accordance with a series of so-called normal forms in order to reduce data redundancy and improve data integrity.