One dimension joined to a fact table several times over, each join playing a different role; think of a date table used for ordered, shipped and delivered dates. As semantic models permit just one live relationship per table pair, the extra roles rely on USERELATIONSHIP with relationships left inactive, or on duplicate tables.
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Terms in this definition
- Fact table
Stores the numbers captured when business events happen, like what each sale brought in; an analytical model rolls these up into measures and slices them by dimensions.
- OVER
Gives a T-SQL window function its window: PARTITION BY, ORDER BY and, if wanted, a ROWS or RANGE frame. Rankings and running totals can then be worked out while every row is kept.
- JOIN
Combines rows from two or more tables in one SELECT, most often by pairing a primary key with the foreign key that refers to it.
- Role
How an actor normally or expectedly behaves, or the part a person takes in a process. A single actor may hold more than one role.
- Date table
Lets you slice and group facts by period. It lists every calendar day of the years it covers exactly once, with nothing skipped, and classic DAX time intelligence only works after it has been marked as a date table.
- Event
Table in Log Analytics where entries from Windows event logs are kept.
- USERELATIONSHIP
Switches on an existing relationship, normally an inactive one, for a single calculation. Only usable within functions accepting filter arguments (CALCULATE, TOTALYTD and so on), and errors if row-level security covers an involved table.