INSIGHTCLOPEDIA

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J

Java online analytical processing (JOLAP)

A Java API for the J2EE platform that can be used for creation, storage, access and management of data in an OLAP application.

Join

A two-table operation in which the data from the two tables of a relational database is merged into one larger and more detailed so-called joined table.

Journal file

A file in which update information is stored to enable roll back and data recovery actions at a later stage. Journal files are often used to take snapshots of the status of a data warehouse at specific times. Journal files are less likely to become corrupt in a system crash than regular files.

Junk dimension

A separate dimension table to group combinations of indicators and flags with low cardinality to avoid a monster star scheme and poor performance. A junk dimension is a composite of a number of small dimensions that exist for the purpose of decoding operational codes. In a situation where there are many such small dimensions, it is possible to merge them …