What is factless fact example?
A factless fact table is a fact table that does not have any measures, i.e. any numeric fields that can be aggregated. For example, if you are modelling product sales, you can have a Sales fact table that will contain the dimension keys and, for example, the “amount” value/measure, to record the amount sold.
What is factless fact table in SSAS?
A factless fact table is a fact table that does not have any measures. It is essentially an intersection of dimensions (it contains nothing but dimensional keys).
When would it be appropriate to use factless fact tables?
Factless fact tables are only used to establish relationships between elements of different dimensions. And are also useful for describing events and coverage, meaning tables contain information that nothing has happened. It often represents many-to-many relationships. The only thing they have is an abbreviated key.
What are non additive facts?
Non-additive Facts are Facts that cannot be summed up for any of the dimensions present in the Fact table. Eg: Facts which have percentages, Ratios calculated. Semi-Additive: Semi-additive Facts are Facts that can be summed up for some of the dimensions in the Fact table, but not the others.
What are semi additive facts examples?
Semi-additive facts are facts that can be summed up for some of the dimensions in the fact table, but not the others. For example if you have the number of items in the warehouse for each day, you can sum up the items for each day (total warehouse of the day), but it make no senso to sum up in the year.
What is junk dimension with example?
A Junk Dimension is a dimension table consisting of attributes that do not belong in the fact table or in any of the existing dimension tables. The nature of these attributes is usually text or various flags, e.g. non-generic comments or just simple yes/no or true/false indicators.
How many attributes does factless fact table have?
There are two kinds of factless fact tables: Factless fact table describes events or activities. Factless fact table describes a condition, eligibility, or coverage.
What is the meaning of Factless?
Lacking facts; inaccurate or fictional
factless (comparative more factless, superlative most factless) Lacking facts; inaccurate or fictional.
What is additive and semi-additive fact?
Additive: Additive facts are facts that can be summed up through all of the dimensions in the fact table. Semi-Additive: Semi-additive facts are facts that can be summed up for some of the dimensions in the fact table, but not the others.
How do you handle non-additive facts?
A good approach for non-additive facts is, where possible, to store the fully additive components of the non-additive measure and sum these components into the final answer set before calculating the final non-additive fact. This final calculation is often done in the BI layer or OLAP cube.
What are additive semi-additive and non-additive measures with examples?
Semi-additive measures can be aggregated across some dimensions, but not all dimensions. For example, measures such as head counts and inventory are considered semi-additive. Non-additive measures are measures that cannot be aggregated across any of the dimensions.
What is semi-additive attribute?
Semi-additive measures are values that you can summarize across any related dimension except time. For example, sales and transactions are fully additive; if you sell 50 yesterday and 10 today then you’ve sold 60 in total. You can add them up over time.
Why do we use junk dimension?
A junk dimension combines several low-cardinality flags and attributes into a single dimension table rather than modeling them as separate dimensions. There are good reasons to create this combined dimension, including reducing the size of the fact table and making the dimensional model easier to work with.
Which statement is true about factless fact table?
1 Answer. A factless fact table is a fact table that does not have any measures. It is essentially an intersection of dimensions (it contains nothing but dimensional keys).
Is Factless a real word?
Factless definition Lacking facts; inaccurate or fictional.
What is additive fact example?
Additive facts are those facts which give the correct result by an addition operation. Examples of such facts could be number of items sold, sales amount etc. Non-additive facts can also be added, but the addition gives incorrect results. Some examples of non-additive facts are average, discount, ratios etc.
What are the three types of facts?
There are three types of facts: Summative facts: Summative facts are used with aggregation functions such as sum (), average (), etc. Semi summative facts: There are small numbers of quasi-summative fact aggregation functions that will apply. For example, consider bank account details.