I am currently developing a data warehouse for a telecom company. I'm wondering what the optimal data warehouse design would be: I would therefore have several fact tables with maximum 25 fact fields which seems more reasonable? I would greatly appreciate any advice or comment or field experience with the 2 options proposed or a 3rd alternative
Fact tables and entities aggregate measuresor the numerical data of a business. To measure data in a fact table or entity, all of the measures in a fact table or entity must be of the same grain.
To obtain the most useful data in a fact table or entity, you should use measures that are both numeric and additive. Using these measures guarantees that data can be retrieved and aggregated, so that the business can make use of the wealth of business data in the database.
Fact tables and entities also contain foreign keys to the dimension tables. These foreign keys relate each row of data in the fact table to its corresponding dimensions and levels.
Fact tables and entities use primary keys that are composite keys. A composite key is made up of a subset of other keys. If a table or entity in a dimensional model uses a composite key, then that table is a fact table or entity.
The use of composite keys causes the table or entity to have a many-to-many relationship with other tables and entities in the dimensional model. Fact table and entity types There are three types of fact tables and entities:Mar 15, · Different Types of tables used in OBIA Different type of tables used in Datawarehouse.
This is important to know whoever is working on the data model. Each type of table has its own set of data. Following are the different types of tables used in OBIA.
Aggregate tables (_A). From SQL to DAX: Joining Tables In SQL there are different types of JOIN, available for different purposes. This article shows the equivalent syntaxes supported in DAX and it was updated in May Mar 07, · Fact tables contain keys to dimension tables as well as measurable facts that data analysts would want to examine Dimension tables are used to describe dimensions; they contain dimension keys, values and attributes.
However, one fact remains the same: you won’t go far without learning about the different types of joints.
Wood joints vary in strength and application, which leads to a conclusion that having a knowledge of an array of different jointing methods is important. Oct 15, · The fact that the plasma arc is contained within the nozzle allows pilot arc plasma cutting machines to cut non-conductive materials such as heavy plastic or glass.
Like HF contact process machines, the plasma torch on most pilot arc plasma cutting tables is hand-controlled. Apr 11, · The facts for this type of fact tables are mostly additive facts.
The first example presented here is a cumulative fact table. B) Snapshot: This type of fact table describes the state of things in a particular instance of time, and usually includes more semi-additive and non-additive facts.