All Interview Cognos Questions Part 2

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1.	What is Data warehouse?   {treenox questions}
	In 1980, Bill Inmon known as father of data warehousing. "A Data warehouse is a subject oriented, integrated ,time variant, non volatile collection of data in support of management's decision making process". Subject oriented : means that the data addresses a specific subject such as sales, inventory etc. Integrated : means that the data is obtained from a variety of sources. Time variant : implies that the data is stored in such a way that when some data is changed. Non volatile : implies that data is never removed. i.e., historical data is also kept.
2.	What is the difference between database and data warehouse?
	A database is a collection of related data.  A data warehouse is also a collection of information as well as a supporting system.
3.	What are the benefits of data warehousing?
	Historical information for comparative and competitive analysis. Enhanced data quality and completeness.Supplementing disaster      recovery plans with another data back up source.
4.	What are the types of data warehouse?
	There are mainly three type of Data Warehouse are : 1) Enterprise Data Warehouse 2) Operational data store 3) Data Mart
5.	What is the difference between data mining and data warehousing?
	Data mining, the operational data is analyzed using statistical techniques and clustering techniques to find the hidden patterns and trends. So, the data mines do some kind of summarization of the data and can be used by data warehouses for faster analytical processing for business intelligence. Data warehouse may make use of a data mine for analytical processing of the data in a faster way.
6.	What are the applications of data warehouse?
	Data warehouse are used extensively in banking and financial services, consumer goods. > Data warehouse is mainly used for generating reports and answering predefined queries. > Data warehouse is used for strategic purposes, performing multidimensional analysis. > Data warehouse is used for knowledge discovery and strategic decision making using data mining tools.
7.	What are the types of data warehouse applications?
	Info processing, Analytical processing and Data mining
8.	What is metadata?
	Metadata is defined as the data about data. Metadata describes the entity and attributes description.
9.	What are the benefits of Datawarehousing?
	The implementation of a data warehouse can provide many benefits to an organization. A data warehouse can : Facilitate integration in an environment characterized by un–integrated applications. Integrate enterprise data across a variety of functions. Integrate external as well as internal data. Support strategic and long–term business planning. Support day–to–day tactical decisions. Enable insight into business trends and business opportunities. Organize and store historical data needed for analysis. Make available historical data, extending over many years, which enables trend analysis. Provide more accurate and complete information. Improve knowledge about the business. Enable cost–effective decision making. Enable organizations to understand their customers, and their needs, as well competitors. Enhance customer servicc and satisfaction. Provide competitive advantage. Provide easy access for end–users. Provide timely access to corporate information.
10.	What is the difference between dimensional table and fact table?
	A dimension table consists of tuples of attributes of the dimension. A fact table can be thought of as having tuples, one per a recorded fact. This fact contains some measured or observed variables and identifies them with pointers to dimension tables.
11.	What is data mart?
	A data mart can contain one fact table to address one subject. In such a case,when a number of data marts are integrated to create a DWH, it is important that the facts in each table mean the same thing. Such facts (i.e., measures or metrics) that have the same meaning in different data marts are called conformed facts.
12.	What are the different types of datasmarts?
	Stand–alone Data Marts : Data marts that do not interact with other data marts are called stand–alone data marts. On the other hand, data marts can be integrated to create a data warehouse. Multi–source Data Mart : A data mart for which the input data is obtained from multiple sources is called a multi–source data mart. Personal Data Mart : A data mart for use by individuals such as Chief Executive Officer (CEO), Chief Technology Officer (CTO) or Chief Financial Officer (CFO) is called Personal Data Mart. Operational Data Store : ODS is a database system that obtains data from different sources, consolidates it and keeps it at a single location. However, it does not have the sophistication of a data mart or a data warehouse for analytical processing. ODS is generally developed as a pre-cursor for ERP systems.
13.	What is fact table?
	A fact table is the central table that contains the measures or facts of a business process.
14.	What is the mapplet?
	Mapplet is a set of transformations that you build in the mapplet designer and you can use in multiple mappings.
15.	What is meant by grain?
	Granularity of data is a very important factor in the design of fact table. In fact table, we can represent data at different atomic levels, called grains.
1.	What is Cognos Impromptu?
	Cognos Impromptu is a tool for generation of business intelligence reports.
2.	What is Cubes?
	A cube consists of a set of ordered dimensions and measures. A cube may have one or several dimensions.
3.	What is query subject?
	A query subject is the basic building block in framework manager. A query subject is a set of query items that have an inherent relationship.
4.	What is Report item?
	Report item is a query item when it is drag and drop into the work area.
5.	What is a query item?
	Query items are mainly used in Reporting and for BI Authors it is the most essential object from the framework manager. These have lot of properties associated with them and are present in query subjects. Query items are similar to subsets of query subjects.
6.	What are the advantages of Cognos?
	Planning, Analysis, Forecasting and Score carding
7.	What are packages?
	Packages are used for reporting.
8.	What is materialized view?
	A view which is physically stored in a database. Materialized views allow query performance to be enhanced by pre calculating costly operations.
9.	What is schema?
	A schema is composed of a set of dimensions and a set of fact relationships.
10.	What is folder?
	Folder contains repository objects such as sources, targets, mappings, transformation which are helps logically organize our data warehouse.
11.	What are the types of report?
	Blank report, List report, Cross report, Chart report, Repeater report
12.	What are Slice and Dice?
	An operation that allows one to select a portion of the data of a fact on the basis of specified values in one or several dimensions.
13.	What is pivot?
	The pivot (or rotate) operation rotates the axes of a cube to provide an alternative presentation of the data.
14.	What are the types of gateway?
	Common Gateway Interface(CGI), Internet Service Application Interface(ISAPI) and Tomcat
15.	What is Cognos Reporting tool?
	Cognos is a reporting tool from IBM which helps in reporting and analysis of various data from a data warehouse.
16.	What are the types of framework manager?
	There are two types of framework manager are : Presentation layer and Physical layer
17.		What are dimensions?
		Dimensions define the structure of a cube. A dimension must have at least one key attribute and other attributes that may define hierarchies.
18.		What are the components of Report Net?
		Report Net components are : Framework manager, Cognos connection, Query Studio, Report Studio
19.		What are the types of hierarchies?
		In Analysis Services, there are two types of hierarchies are : Attribute hierarchies and User defined hierarchies.
20.		What is slice?
		The slice operation performs a selection on one dimension of a cube, resulting in a sub cube.
21.		What are the types of prompt?
		Value Prompt, Textbox, Select and search, Date, Time, Date and time, Interval, Generated Prompt.
22.		What is Cognos Connection?
		It is a Web portal for Cognos 8 and a component which interacts with the Content Store. It is a frontend to publish, find, manage, organize, and view organization's business intelligence data.
23.		What is framework manager?
		Frame manager is a development tool to create the end-user layer used by authors to build their BI objects.
24.		What is OLAP designer?
		OLAP Designer is a development tool used to model and create multidimensional databases. A multidimensional database, often referred to as a cube, is a highly compressed database and contains summarized information that is optimized for analysis.
25.		What is metrics designer?
		Metrics Designer is a development tool used to model and deploy scorecards and related data loading procedures.
26.		What is meant by drill across?
		The drill–across operation executes queries involving more than one cube.
27.		What is meant by drill through?
		The drill–through operation allows one to move from data at the bottom level in a cube to data in the operational systems from which the cube was derived.
28.		What is meant by drill down?
		The drill-down operation performs the operation opposite to the roll-up operation, i.e., it moves from a more general level to a detailed level in a hierarchy, thus presenting more detailed measures.
29.		Define data mining?
		A data mining dimension provides support for dimensions that result from data mining models.
30.		What is Metrics Designer?
		Metrics Designer is a development tool used to model and deploy scorecards and related data loading procedures.
31.		What is cognos powerplay?
		Cognos powerplay is for multidimensional on–line analysis of data.
32.		What is the use of cognos decision stream?
		Cognos decision stream is a tool for extraction, transformation of loading of data from the source databases to the target database.
33.		What is the use of cognos scenario?
		Cognos scenario is used to find the hidden trends and patterns in data.
34.		What is meant by drilling Up?
		Drilling down is adding grouping columns from the dimension tables, then drilling up is subtracting grouping columns.
35.		What are the three important fundamental themes in a data warehouse?
		The three most important fundamental themes are : Drilling Down, Drilling Across and Handling Time
36.		How to create reports?
		Use Report Studio to create more advanced business reports.
37.		What is the security module used in Cognos?
		The security module used in Cognos is Cognos access manager.
38.		What is catalog ?
		A catalog is a file containing the information (Database tables) that Impromptu users need to create reports.
39.		What are the types of catalogs in Cognos?
		There are four types of catalogs in Cognos. They are : Personal, Distributed, Shared and Secured
40.		What are the differences between Reporter report and Explorer report?
		In a Cube, you can either modify or explore. Reporter is used to modify where as explorer is used to explore the cube.
41.		What is cognos connection?
		Cognos Connection is used to monitor, configure and optimize a Cognos 8 BI installation through a web interface. It is the same tool used by Consumers, but contains other advanced options for administration.
42.		What is cognos configuration?
		Cognos Configuration is the Cognos 8 BI administrative tool that is used to define the behavior of a Cognos 8 BI installation. It is used to manage configuration parameters.
43.		What are the types of folder?
		There are three main types of folders are : Standard folder, Package folder and Metrics folder
44.		What is the difference between standard and metrics folder?
		Standard Folder : This is a container for other folders and/or BI objects, and is used for organizational purposes. It will behave just like a folder on your local computer, but will operate like a web page with active links. A bright yellow icon specifics Standard folders. Metrics Folder : Metrics folders arc used by the Metrics Studio to store metrics-related information. While the standard behavior upon selecting the other two folder types is to show their contents, a Metrics Folder will open up directly into Metrics Studio. A dark blue icon with colored dots specifies Metrics folders.
45.		What is query studio?
		Query studio are used to perform ad hoc queries.
46.		What is difference between drill through and drill down?
		The drill through operation allows one to move from data at the bottom level in a cube to data in the operational systems from which the cube was derived.  The drill down operation performs the operation opposite to the roll-up operation, i.e., it moves from a more general level to a detailed level in a hierarchy, thus presenting more detailed measures.
47.		What is the difference between a cascading report and drill through report?
		Cascading prompt means to extract the data from one prompt to using values from another prompt. Drill through report means to extract the data by selecting a column in a report, means to get the detailed information by clicking that column data.
48.		What are the types of studio?
		There are five types of studio are : Query Studio, Metrics Studio, Analysis Studio, Report Studio and Event Studio
49.		What are Cognos connection initial page components?
		The page can be broken down into three major sections : 1) The Studio Toolbar 2) The Utilities Toolbar 3) The Tab Navigator
50.		What is the difference between macros and prompt?
		Macro is set of instructions to run report. Prompt provide a way to dynamically change the reports.
51.		What is Cognos scenario?
		Cognos scenario is a tool that is used to find the hidden trends and patterns in data.
52.		How to create cubes in transformer?
		Cube can be created by using different data sources.
53.		What are the components of Report Net?
		There are four components of report net are : Framework manager, Cognos connection, Query Studio and Report Studio
54.		What is transformer?
		Transformer is used for building the Cubes (Multidimensional Structure used for OLAP processing).
55.		What is model?
		A model is a complete set of query objects and query subjects that are used for reporting.
56.		What is IQD?
		IQD stands for Impromptu Query Definition. It is report save extension with .iqd it is use for creating a cube in power play transformer.
57.		What is cascading prompts?
		Cascading Prompts allows a user to use values selected from one prompt to filter values in another prompt.
58.		What is the use of charts?
		Charts are a graphical way of presenting information. Use charts to reveal trends and relationships that are not evident in tabular reports.
59.		What are the filters in Framework Manager and Report Studio?
		Filters in framework manager are : Standalone filters and Embedded filters Report studio Filters are : Detail filters and Summary filters
60.		What is difference between content store and content manager?
		A content store is a data base which stores the meta data of the reports. Content manager is a service which is available in dispatcher. which it manages the security.
61.		What is Cognos 8 BI?
		Cognos 8BI is a powerful suite of products that focuses on transforming raw data into powerful information for business decisions. Cognos 8 BI can be used across all levels in an organization, from users looking for pre-defined reports to analysts with complex data requirements.
62.		What are package folders?
		This folder is similar to a Standard Folder, but internally it contains pre-defined business rules and metadata related to sources of information. It is used by the Studios to create new queries, reports, analyses, etc. A dark blue icon specifics Package folders.
63.		What are components of report studio?
		There are four components of report studio are : Insertable Objects pane ,Properties pane ,Explorer bar and Report Viewer
64.		What are the types of security?
		There are three different types of Security are : Data security: Create a security filter and apply it to a specific query subject. Object security: Secure an object directly by allowing users access to the object, denying users access to the object, or keeping it hidden for all users. Package security: Apply security to a package and identify who has access to that package.
65.		What is metrics designer?
		Metrics Designer is a development tool used to model and deploy scorecards and related data loading procedures.
66.		What is query studio?
		Query Studio is a very user friendly ad hoc query tool that allows users to easily access information. With Query Studio, the user drags and drops fields to execute queries, and with multiple available options at a touch of the mouse, it can group data, create summaries, display charts, filter information and export data.
67.		What is metrics studio?
		Metrics Studio is a powerful scorecard tool that allows for the creation and monitoring of goals through an organization.
68.		What is analysis studio?
		Analysis Studio is the user friendly tool used to quickly analyze summarized information with powerful dimension and variable crossing for complex analysis, discovery of trends and forecasting.
69.		What is report studio?
		Report Studio is the professional report authoring tool. The tool allows for the development of pixel perfect reports, such as invoices and statements, as well as very complex layouts, such as those required for enterprise dashboards.
70.		What is event studio?
		Event Studio is a monitoring tool that allows for the definition of agents that will monitor certain user-defined events and will execute tasks accordingly. They can be saved to Cognos as ″agents″.
71.		What are the types of user roles?
		The users of Cognos 8 BI can be grouped into four major roles based upon their respective business and technical requirements.Consumers, Authors, Developers, Administrators
72.		What are repeaters?
		Repeaters are tables in which you can insert items that are repeated when you run the report.
73.		What are cross tab reports?
		Crosstab reports are reports that show data in rows and columns. However, the values at the intersection points of rows and columns show summarized information rather than detailed information.
74.		What is list report?
		A list report is a report that shows data in rows and columns. Each column shows all the values for a query item in the database or a calculation based on query items in the database.

What is
use of Field Set present in toolbox?
Field Set is nothing but a container. like a block. The difference between a block and field set is "header". The block doesn't contain a header but the field set contain the header. in that header we can enter the text item whatever we want to show in the report.




diff b/w
dimension and regular dimension
dimension are descriptive information. for example customer name,address.  where as regular dimensions are used to create the hierarchies in dimensions. for example let us take product dimension.
u can create hierarchies in product dimension using regular dimension. u can create hierarchies as product number,product name, product line code,product description.
the regular dimensions are used in analysis studio for drill down and drill up methods




What is
the use of 'individual data source' option while using filter in query studio?



When we use individual data source, it means we are applying filters over the values in the DWH directly before they are brought to cache. In the cache the values are summed up. So it will apply the filter before summing up the value. 
Eg.
Suppose we are creating a report
Product     Quantity
Lux          50
Pantene      60
 
In the main data base these values are
Lux     10
lux     15
lux     15
lux     10
 
so wen we are using individual data source the filter will work on the main data base value and not the summed value that we bring to the report from cache.




What is
member Description?
this is comes under DMR models.
Its description about Business Key.




what is
meant by roll up and roll back in dataware housing?
roll up means going from lowlevel concepts to high level concepts and drill down(roll back) means going top to bottom in concept hierarchies




Diff b/w
surrogate Key and Primary Key?
Primary keys are used in OLTP whereas surrogate keys are used in OLAP schemas.PKs hold some business meaning whereas SKs does not hold.PKs contain both numeric as wellas non numeric values whereas SKs contain only simple numeric values.




drillthrough
vs master detaild report,which one is the best by performance?
i Said Maseter Detaild is faster than Drill through Bcz it is not navigate to another repot but Drill through it is navigate from one repot to another repot i.e parent to chaild report.




What are
the Adv of Star Schema and Snow Flake Schema?
Star Schema:
Definition: The star schema is the simplest data warehouse 
schema. It is called a star schema because the diagram 
resembles a star with points radiating from a center. 
 
A single Fact table (center of the star) surrounded by 
multiple dimensional tables(the points of the star).
Advantages:
 
Simplest DW schema 
Easy to understand 
Easy to Navigate between the tables due to less number of joins. 
Most suitable for Query processing 
Disadvantages:
Occupies more space 
Highly Denormalized 
 
Snowflake schema:
 
Definition: A Snowflake schema is a Data warehouse Schema 
which consists of a single Fact table and multiple 
dimensional tables. These Dimensional tables are 
normalized.A variant of the star schema where each 
dimension can have its own dimensions.
 
Advantages: 
 
These tables are easier to maintain 
Saves the storage space.
Disadvantages:
 
Due to large number of joins it is complex to navigate 
 
Starflake schema - Hybrid structure that contains a mixture 
of (denormalized) STAR and (normalized) SNOWFLAKE schemas




how to
change the colour of the bar in charts...?
Go to Pallete, then select the color, gradient and pattern depending on the style you want.







wt is
the differnce between Block & conditional block ?
Block:-- is the object in which u can place the other 
cognos abject as list crosstab ,graph etc..
A container into which you can insert other objects
 
and conditional Block:--
Specify a variable based on which objects inserted into a 
block can be conditionally rendered. Applies only to 
conditional block objects that you insert in a report .




Can we
create a web page where the report directory and the output can be viewed
directly across cognos connection?



Yes. You can create a web page, where report directory and output can be viewed. 
 
You need to goto-> IBM Cognos Administer or MyHome and select the new page button and edit the properties of the selected button as per the requirement. Here you need to select the link of the report which you want to be added to this page and as a report directory and view the result of 
the report with in the portal page which you created. You can give the name tot he created pade as you desired.




Difference
betwween cognos report net architecture and cognos8 architecture
cognos report net and cognos8 both architecture are same.But in cognos 8 architecture (application tier) contains Metric Studio and Analysis studio, also in data tire it contains one more store metric store.




Can any
body suggest me that Drill through of packages is possible? If yes, how it can
be done?
yes it is posible you can drill through one package to  another package even u can drill through one package in report studio to another package in query studio i mean drill through is posible one studio to other studio i mean report studio to query studio but when u apply the drill throuth for one package to another package u have to give traverse permission without giving this permission it is not posible if u apply drill through for same package traverse permission is not required but for one package to another package or else one studio to another studio it is mandatory




what is
Cognos Visualizer?
Cognos visualizer  is a tool for creating charts(bar,pie,histogram....)& maps using datasources(datafiles like mdc,iqd,csv,excel etc).




How to
use Cascade Macro in Report studio? Anybody know about Cascade Macro & and
the procedure to use?
Using Cascade Macro, we can create more than one condition (ie. Sales<500 or Sales >2000 or 2000>sales>500).End user may choose the condition and based on that he can get the Report.




can any
body explain clearly how to explain any (sales) project in interview.actually
feom where report developer work starts?pls reply as soon as possible.
IF I were u wll expalin my proj like this
 
I working for ....(name of the proj) proj,client is ....(name of the client), which is saless and distribution domain, technology in my proj is .......(like Informatica 
as ETL TOOL, BI TOOL AS COGNOS, Backend database is ORacle)
 
describe a bit about ur client business a bit.
( suppose for a mall inventory level, itemsold per week and pregressive businessd timings like festivals)
 
as a report author i developed ..... these kind of reports , which are very useful for enduser to take business decisions.
 
Generally DWH group contains
1.database team( like oracle)
2.ETL team
3.BI team
4Testing Team
5.Support Team
 
team 1: perople generally load the data into database and architect will prepare ER model for that and constraints ofthe table.
 
Team2: once data entered into the dbase, Etl architect prepares star schema for Dwh and Etl developers extract data from dbase and made some transformations (depend on business requirements like scrubbing) and load that data 
into Datawarehouse in the form of datamarts.
 
Team3. Bi architect extract the data from Dwh and prepares a model (universe)and work wll be assigned to Report author to populate the data in the form of the reports asd per end user requirement.
 
Team 4: testing team generally test the report and if any bugs found dt will be forwarded to support team.
 
Team 5. this team people try to resolve those issues if it is not possible for them again it wll transformed to Etl team.
completely this is a cyclic process.




 is it possible to display the column names in
first page but not in remaining pages i.e if a report contains 10 pages column
names should be displayed in 1st page but not remaining pages ( 2 to 10)
First hide the header of the list and now create a repeater table with the list header names and uncheck the pagination of the reapter table and format the repeater table and list.

write a
query to display to 10 max record from the employee table?
select * from (select * from employee order by salary desc)where rownum<11;




what are
typees of dimensions
there r 10 types of dimension
1.primary dimension
2.secondry dimension
3.degenerated dimension
4.conform dimension
5.slowly changing dimension
6.fast changing dimension
7.monster dimension
8.junk dimension
9.role playing dimension
10.large dimension




Can you
please tell me the limitation of Excel file when exporting from report to
Excel? I can export to HTML and PDF but I can't export to Excel. The report is
more than 13000 rows. When exporting to Excel, system can view it. After that,
I save the report to an Excel file. The size of Excel file is more than 11 MB.
But I can't view this file by Excel.
The limitaion for Excel is 65000 rows if U are using any version Prior to Cognos 8.3.If its C8.3,then in Excel 2007 format alll these estrictions are overcome.Please check ur IE settings too....




What is
the difference between macro & Parameter
Parameter: Specifies the parameter that is satisfied by values chosen in the prompt control.
 
Applies to Date & Time Prompt, Date Prompt, Generated Prompt, Interval Prompt, Select & Search Prompt,Text Box Prompt, Time Prompt, Tree Prompt, Value Prompt
 
Macro:A macro is a runtime object, which uses the parameter maps and sesssion parameters in developing the conditional query subjects.




in
reportnet how u burst the reports for every 5th day, 10 th day, 15 th day, 20
th day
set burst options in report studio,
enable the report for bursting in Cognos connection,
create 4 report views for that report,create a shcedule for each report view - the 1st for every 
5th day, the 2nd for every 10th day, the 3rd for every 15th day, & the 4th for every 20th day.




what r
the filters in fwm and report studio
filters in framework manager are 
1.standalone filters
2.embeded filters
 
in report studio are 
1.detail filters
2.summary filters




What is
a Conformed Dimension?
Conformed Dimension :- A dimension is reused by more than one fact table is called conformed dimension.




Difference
between Express authoring mode and Professional authoring mode?
The Professional authoring mode gives users access to the full range of Report Studio functionality. In this mode, you can create any report type, including charts, maps, lists, and repeaters, using any data source (relational or multidimensional). This mode contains a superset of the features available in the Express authoring mode. However, 
you cannot view live data.
 
The Express authoring mode provides a simplified and focused Report Studio interface. It is designed for non-technical users to create traditional financial and management statement reports. This mode allows access to dimensionally-modeled data and uses a member-oriented data tree, by default. 
 
This authoring mode allows you to see live data and 
supports crosstab reports. It contains a subset of the features available in the Professional authoring mode. 
When you are in the Express authoring mode, if you open a report that was authored in the Professional authoring mode, you can see the objects that can be inserted only in the Professional authoring mode, such as charts, maps, and lists. However, you cannot modify these objects.




what was
the actual purpose of portfolio in cognos ?
Portfolio is a component comes with the cognos EP 7 
series.The main objective is to enable the companies to quickly organize and deploy the cubes,reports and queries etc.




In
framework Manager, what is a stitch query and is it good or bad?
in frame work manager, stitch query is nothing but it will stitch the two querys.
 
for example i have 2 querys like Q1 and Q2 and i stitch these 2 querys and found Q3 with the full outer join




whis
meant by Thumbnails on cagnos?
Thumbnails which will limit the data extracted from the data source.
Thumbnails are used to test the data retreval for the report. Insted of reading entire data base we use Thumbnails to limit the data
Mostly Thumbnails are used for testing the report.

diff b/w
layout calculation and query calculation
Query calculation:by using query calculation we can add new data items in report with the help of exesting query items or data items
Layout calculation:it's a run time calcolation like adding page number, time, dynamic heading to the reportex:if u add date2string(Today()) function in report we will get 2010-09-26 date in output




what is
logs in cognos
while creating reports or creating models  logs have all information till session closed




what is fact less fact give me proper example?
A fact-less fact is a fact table in which only primary keys of the dimension tables are present as foreign keys but no measure/fact columns.
There are 2 types of factless fact table:
a) Event Tracking Tables: A table that records an event. 
Example: A table that records student attendance. It contains date_key, student_key, teacher_key, course_key,without any measure section.
b) Coverage Tables: A table to answer questions about things that didn't happen. 
Example: An ordinary fact table cannot answer questions like "Which products were on promotion that did not sell?", because it contains only the records of products that did sell. A table contains date_key, product_key, store_key, promo_key and without measure section is used to answer such questions.