Monday, April 30, 2007

Database

The term "database" originated within the computing discipline. Although its meaning has been broadened by popular use, even to include non-electronic databases, this article is about computer databases. Database-like records have been in existence since well before the industrial revolution in the form of ledgers, sales receipts and other business related collections of data.
The central concept of a database is that of a collection of records, or pieces of knowledge. Typically, for a given database, there is a structural description of the type of facts held in that database: this description is known as a schema. The schema describes the objects that are represented in the database, and the relationships among them. There are a number of different ways of organizing a schema, that is, of modeling the database structure: these are known as database models (or data models). The model in most common use today is the relational model, which in layman's terms represents all information in the form of multiple related tables each consisting of rows and columns (the true definition uses mathematical terminology). This model represents relationships by the use of values common to more than one table. Other models such as the hierarchical model and the network model use a more explicit representation of relationships.
The term database refers to the collection of related records, and the software should be referred to as the database management system or DBMS. When the context is unambiguous, however, many database administrators and programmers use the term database to cover both meanings.
Many professionals consider a collection of data to constitute a database only if it has certain properties: for example, if the data is managed to ensure its integrity and quality, if it allows shared access by a community of users, if it has a schema, or if it supports a query language. However, there is no agreed definition of these properties.

Monday, April 02, 2007

Personal property

Personal property is a sort of property. In the common law systems personal property may also be described has chattels. It is distinguished from real property, or real estate. In civil law systems personal property is can be called as movable property or movables, any property that can be moved from one location to another. This term is in distinction with immovable property or immovable, such as land and buildings.

The distinction between these kinds of property is important for a variety of reasons. Generally one's rights on movables are more attenuated than one's rights on immovable. The statutes of restrictions or prescriptive periods are usually shorter when trading with personal or movable property. Real property rights are usually enforceable for a longer period and in most jurisdictions real estate and immovable are registered in government sanctioned land registers. In some jurisdictions, rights can be registered against personal or movable property.