By Moran R
Read or Download Oracle9i Security Overview (Part No. A90148-01) (Release 9.0.1) PDF
Best databases books
It doesn't matter what DBMS you're using—Oracle, DB2, SQL Server, MySQL, PostgreSQL—misunderstandings can continuously come up over the ideal meanings of phrases, misunderstandings that may have a significant influence at the good fortune of your database tasks. for instance, listed below are a few universal database phrases: characteristic, BCNF, consistency, denormalization, predicate, repeating workforce, sign up for dependency.
Extra resources for Oracle9i Security Overview (Part No. A90148-01) (Release 9.0.1)
Logical level (step 2). At this stage, the conceptual schema is translated into the data model of a particular DBMS. In the context of relational databases, one follows some simple transformation rules, and describes the relational schema with the data definition language (DDL). Generally speaking, within a DBMS environment, manipulating data is done through expressing queries and other operations (updates, inserts, and so on) in the data manipulation language (DML). One of the reasons for the success of relational DBMS is the existence of a widely accepted query language named SQL, uniformly used in all relational systems.
First, the space of interest is Rd , together with the Euclidean distance. We refer to it as the Euclidean space, and, unless otherwise specified, we assume that dimension d is 2. Points are elements of this space. A point has a pair of (Cartesian) coordinates that, according to common use, we denote as x (the abscissa) and y (the ordinate). Although points in the Euclidean plane are quite useful to represent the location and shape of objects of the Earth’s surface, it should be underlined that the latter is a globe (hence a curved surface), and that we need a conversion, called a map projection, to map geographic entities onto a planar representation.
For instance, the input can be a known set of customer locations, a known transportation system, or a known set of available plots on which to build. The output is the best location to maximize sales. Allocation. This problem (dual with the location problem) deals with the allocation of quantities (resources) among supply and demand points. Typical applications are geomarketing applications and urban planning. Location/allocation combination. The location and allocation functions are often used simultaneously in many GIS applications.