DRAFT

Glossary

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Index A B C D E F G H I J K L M N O P Q R S T U V W X Y Z $ Glossary

Data dictionary

  • An information structure that defines the organization of a database including the list and description of each element of the database such as columns, data types, memory allocations for data storage, etc…

Data files

  • Files that contain actual data, rather than meta-data or other data descriptions. See meta-data and data.

Data mart

  • A departmental or subject-specific subset of data of a data warehouse. See data warehouse.

Data mining

  • The process of finding patterns or trends in a collection of data.

Data modeling

  • The development of rules that cover data entities (objects such as relationships, tables, columns, data integrity, etc.) of a database management system.

Data set

  • A collection of data entries where each entry contains a group of data items. Also called a table.

Data source file

  • An initialization file that stores the location of data on a server and the transport method used to access the data.

Data source name (DSN)

  • DSN; in ODBC, the name of the origin (e.g., of a file, database, document, etc.) of transmitted data.

Data type

  • The characteristic description of data, be it alphabetic, numeric, integer, decimal, character, string, etc.

Data type discrepancy

  • Condition in which data stored in a particular field does not match the DBMS data type defined for that field.

Data warehouse

  • A voluminous collection of summarized consistent data, usually historical in nature, used for only data analysis rather than data processing
  • A database designed and optimized for OLAP.

Data-only option

  • An option supported by the OmniAccess update routines (oainsert, oadelete, and oaupdate) that disables the real-time updating of OMNIDEX indexes. This option is useful when updating a high volume of records. Data-only updates must be followed by a DBINSTAL B or INDEX operation to update the OMNIDEX indexes.

DataSource

  • A collection of information used by the ODBC software to connect to a database, required before accessing databases from a container application such as Microsoft Word.

Decompile

  • in OMNIDEX, the process of reverting a compiled Environment Catalog file to an Environment source file using the utility OADECOMP.

Denormalization

  • The process of introducing duplication of data within a relational database (which is typically normalized), used in data warehouse applications to avoid the inefficiencies of cross-table join operations. See normalization.

Detail data set

  • Child table.

Detail Record

  • A record in a child table. See DR Domain.

DI keys

  • Distributed Index key. See distributed index.

Dimension table**

  • A parent table with a unique key that provides keyed access into a child (fact) table;
  • Tables that contain descriptions for codes in fact tables.

Direct access

  • The process of locating a record or row based on its location on a storage device, which is fast but requires an exact key match. See hashed access and hashed key.

Disconnect

  • The process of disconnect from an Omnidex Environment or from a network connection.

Distributed index

  • An indexing option for Omnidex, or MDK indexes, in which the index is stored as a separate file, essentially creating an IMSAM, or ASK key;
  • An ASK Index installed through an MDK Index process with ;DI option which can be used essentially as an MDK Index, including on-line index maintenance and optimization like an MDK Index, and also aggregation as on an ASK Index.

Domain

  • A parent table and any child tables that were linked (prejoined) to it during Omnidex installation;
  • A single, unjoined table with Omnidex indexes installed on it;
  • A a single data set installed with multiple keys;
  • An association of several data sets installed with multiple keys and linked during installation. Also called an Omnidex domain. See SI domain and DR domain.

DR

  • See Detail Record.

DR domain

  • An OMNIDEX domain that consists of one detail data set, or child table, that has not been linked to a master data set, or parent table. A DR domain child table can also be part of RS (Record Specific) domain. See Hybrid-DR domain and domain.

Drill down

  • In data analysis, the process of narrowing data to retrieve specific underlying detail;
  • In OMNIDEX, successive iterations of adding criteria to a query, refining a search to the exact subset of required data.

Driver Manager

  • Software written by Microsoft and installed when installing ODBC applications;
  • Software accessed by container applications such as Excel which initiates the appropriate ODBC driver such as the OMNIDEX ODBC Driver.

DSN

  • DataSource Name; see data source name
 
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glossary/d.txt · Last modified: 2012/10/26 14:24 (external edit)