Download An Extended Entity-Relationship Model: Fundamentals and by Martin Gogolla PDF

By Martin Gogolla

This textual content provides a accomplished advent to a longer Entity-Relationship version either on a conceptual and on a proper, mathematicallevel. as well as the primitives given by way of the knowledge version the textual content introduces a language for the formula of constraints that allows you to limit database states to constant ones. The textual content explains an implementation of the procedure selected within the common sense programing language PROLOG and discusses during this context the computational energy of the proposedcalculus. The prolonged Entity-Relationship calculus is used to outline the that means of the relational question language SQL. a pleasant characteristic of the strategy is that it turns into attainable to end up language houses on a legitimate mathematical basis.

Show description

Read Online or Download An Extended Entity-Relationship Model: Fundamentals and Pragmatics PDF

Best sql books

Microsoft SQL Server 2000 Programming by Example

SQL Server 2000 Programming by way of instance presents transparent and concise examples of uncomplicated programming strategies utilized in SQL Server 2000 basically utilizing Transact-SQL. whether you are a whole amateur to SQL Server 2000 programming, you are going to profit through analyzing in the course of the book's logical strategy. SQL Server 2000 is brought and explored, database constitution is designed and equipped, and eventually various programming recommendations are studied and reviewed.

Professional SQL Server 2005 CLR Programming: with Stored Procedures, Functions, Triggers, Aggregates and Types

SQL Server 2005 bargains the potential to write down code in a . internet language that may be compiled and run within SQL Server. CLR Integration, or SQL CLR, enables you to create kept tactics, user-defined kinds, triggers, desk valued capabilities, and aggregates utilizing a . web controlled language. you could learn and write to assets outdoor of SQL Server and revel in a tighter integration with XML, internet prone, and easy dossier and logging services.

PostgreSQL 8 for Windows (Database Professional's Library)

One of the simplest ways to establish a PostgreSQL database server on WindowsGet up-and-running on PostgreSQL speedy utilizing this hands-on consultant. packed with real-world examples, PostgreSQL eight for home windows provide you with sensible, step by step information on fitting, configuring, and utilizing PostgreSQL 8--the full-featured, open-source database administration system--on home windows systems.

Microsoft Excel 2013 Building Data Models with PowerPivot

Your advisor to speedy flip information into effects. rework your talents, info, and business—and create your personal BI ideas utilizing software program you realize and love: Microsoft Excel. enterprise intelligence (BI) specialists take you inside of PowerPivot performance for Excel 2013, with a spotlight on actual international eventualities, problem-solving, and knowledge modeling.

Additional info for An Extended Entity-Relationship Model: Fundamentals and Pragmatics

Sample text

1 are both terms of sort T O W N having the single free variable la. Both terms evaluate to the town that participates in the relationship assigned to the variable la by a given a. S E C T I O N 3C. T E R M S A N D F O R M U L A S 43 3. WATERS(r) is a term of sort W A T E R S having the single free variable r. This term evaluates for a given a to the water corresponding to the river assigned to r by a. Indeed, we have assumed every river to be also a water (by an additional constraint). The above is not a correct term in the calculus of [Hohg0] because it does not allow this form of conversion.

The function sort determines the sort of every term. The function free yields the set of free variables for a given term. The free variables are in fact the ones that 42 C H A P T E R 3. E X T E N D E D E N T I T Y - R E L A T I O N S H I P CALCULUS have to be given a value by an assignment. The assignments to non-free variables are not essential for the evaluation of terms. In the cases (i) - (v) the free variables are obvious. , dk. For the sake of simplicity we assume a formula f being omitted to be the tautology true.

R I V E R for a concrete relationship assigned to the variable la by a. The variable c is free in cname(c) and the variable la is free in distance(la). 6. pname(head(c)) is a term of sort string, since we have head : C O U N T R Y - + - P E R S O N and pname : P E R S O N -+ string, c is the only free variable. This term evaluates to the name of the head of the country assigned to c by a given a. 7. ministers(c) is a term of sort list(PERSON) having the single free variable C. 8. CNT(ministers(c)) is a term of sort int having the single free variable c.

Download PDF sample

Rated 4.44 of 5 – based on 19 votes
Category: Sql