Web hosting contract - Unique key A key created on a field containing
Unique key A key created on a field containing only unique values throughout an entire table. UNIX An operating system that is far more complex and far more difficult to manage than an operating system like Microsoft Windows. UNIX is, however, far more versatile and far more powerful but also much more expensive. UPDATE The command used to change data in records in tables. Update anomaly An error caused when a database allows an error to be generated, by updating incorrectly across a primary and foreign key relationship. A record cannot be updated in a master table unless all sibling records, in all related child tables, are updated first. Note that changes can be propagated to sibling records in child tables, using cascading. User See End-user. User-friendly Describes a software application (or otherwise) that allows ease of use for the non-computer literate, or end-user population. Validation check. See Check constraint. Variable-length records Every record in a table does not have to be the same byte-length. This allows use of datatypes, such as variable-length strings (CHAR VARYING(nn)). Most modern relational database engines use variable-length records. Variable-length string A string with 0 or more characters, up to a maximum length of characters. View A logical overlay containing a query, executed whenever the view is accessed. Repeated query execution can make views very inefficient in busy environments. WHERE clause A clause that is an optional part of the SELECT statement, the UPDATE, and DELETE commands. The WHERE clause allows inclusion of wanted records, and filtering out of unwanted records. Windows Explorer A Microsoft Windows tool used to view and access files on disk. 419 Glossary
We recommend cheap and reliable webhost to host and run your web applications: Coldfusion Web Hosting services.