V


value

(1) The alpha or numeric content of a field or variable.

(2) The smallest unit of data manipulated in SQL.

(3) A specific data item at the intersection of a column and a row.



variable

A data element that specifies a value that can be changed.



variable-length string

A character, graphic, or binary string whose length is not fixed but can range within set limits. Also referred to as a varying length string.



version recovery

The restoration of a previous version of the database, using an image that was created during a backup operation.



view

(1) A logical table that consists of data generated by a query. A view is based on an underlying set of base tables, and the data in a view is determined by a SELECT statement that is run on the base tables. Contrast with base table.

(2) A way of looking at the information about or contained in objects. Each view might reveal different information about its objects.



Visual Explain

A tool that provides a graphical interface for database administrators and application programmers to display and analyze detailed information on the access plan of a given SQL statement. The tasks provided by this tool can be accessed from the Control Center.



volatile table

A table for which SQL operations choose index access whenever possible.





Understanding DB2(R. Learning Visually with Examples)
Understanding DB2: Learning Visually with Examples (2nd Edition)
ISBN: 0131580183
EAN: 2147483647
Year: 2004
Pages: 313

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