Building the Essbase Outline [ 70 ] Types of dimensions In Essbase, there are two types of dimensions, the rst and most common dimension type is the Standard dimension. The other less common dimension type is called an Attribute dimension. Both are explained here. Standard dimension Standard dimensions are derived from the main business data components (or data categories we described earlier) and are then dened in a database cube. Some of the Standard dimensions in our example database are: TOTAL VEHICLES, MEASURES, CALENDER PERIODS, TOTAL MODEL YEARS, CUSTOMERS, MARKET, and SCENARIO. These dimensions can be tagged as Accounts, Time, and Country types. Some dimensions are not associated with any type of special dimension types and are considered general dimensions. Briey, let's explore the different ways you can tag a Standard dimension and their uses. The Account dimension type When you tag a dimension as an Account type, you are telling Essbase that this dimension will be used for your nancial measures or metrics. Available to the Account dimension are several accounting specic tags such as the Time Balance option that uses the Time dimension to calculate period specic data or the Two Pass Calculation option which will calculate the data in two passes when components of that data must be calculated rst from the existing data. The Time dimension type The Time dimension type is the dimension where you dene the periods used to calculate and report your data. This would typically be the dimension where you store calendar periods. The Time dimension also supports several of the Accounts dimension functions. The Country dimension type A dimension tagged as a Country dimension allows you to analyze your data across multiple countries, if you desire. You can also set the currency for each country to get true and current nancial data analysis for each local market dened in your database. This material is copyright and is licensed for the sole use by Paul Corcorran on 5th July 2009 8601 ave. p #1, , lubbock, , 79423 Download at Boykma.Com Chapter 3 [ 71 ] No dimension type or general dimension Not all dimensions need to have a specic identier tag. You can always create a general dimension that you can use for any variety of data descriptor purposes. Most of your dimensions will be general dimensions. The Currency Partition dimension type This type of dimension is used for currency conversion in your database. The database would contain all nancial data represented in a base currency. The Currency Partition dimension is used to allow local currencies from other regions to be brought in from a separate Essbase database. The Currency Partition dimension is specically designed for currency conversion applications and is not always necessary to achieve your desired results. Careful preparatory investigation upfront is always recommended. Below is a sample screenshot showing an outline containing dimensions that are tagged with the various available dimension types. Once the dimensions are properly set, you will see the dimension type listed in the database outline next to the dimension name. The specic dimension tags are for convenience and enhanced functionality. However, many of these options were not available in earlier versions of Essbase so you would have needed to code your own functionality. This material is copyright and is licensed for the sole use by Paul Corcorran on 5th July 2009 8601 ave. p #1, , lubbock, , 79423 Download at Boykma.Com Building the Essbase Outline [ 72 ] The Attribute dimension There is a dimension type known as an Attribute dimension type. The Attribute dimension is not a full blown standard dimension and in fact must be associated with a standard dimension. The Attribute dimension allows you to analyze your data with even ner granularity by adding data characteristics (for example, color) to your Total Vehicle dimension. If it is not an Attribute dimension type then it is some form of Standard dimension. Dense and Sparse dimensions As we described before, the data stored in an Essbase database is stored in a manner conceptually similar to that of a Rubik's Cube. Because of this structure, the folks at Oracle have devised a method of dening your outline dimensions and their data density to Essbase. Therefore, your database can be more efcient in the way it loads, stores, calculates, and retrieves your data. The distinction between Dense and Sparse dimensions allows Essbase to efciently handle large amounts of data that is not evenly spread across the data blocks. It is this efciency that allows Essbase to offer the slice and dice style of data access, while still maintaining high performance for fast data processing and retrievals. Correctly set Dense and Sparse dimension attributes have a dramatic effect on overall memory usage and system performance! • In a Sparse dimension, the data does not exist for the better part of the member combinations. For example, all vehicles may not be sold in all of the countries • A Dense dimension has a very high percentage of available data cells lled with data. First of all, you will need to consider whether a database dimension is Dense or Sparse in an Application|Database that has been created using the BSO. All dimensions in an ASO database are Sparse by default. When you have an Essbase database created using the BSO, Essbase allows you to describe your dimensions as either Dense or Sparse with the following understanding. Some data cubes, created roughly by dimension, are not fully populated with data. In fact, for the most part, the typical Essbase multidimensional database's cube always has a relatively Sparse concentration of data at the overall database level. It would be an extreme rarity to nd your data densely populating every available cell with a stored value. This material is copyright and is licensed for the sole use by Paul Corcorran on 5th July 2009 8601 ave. p #1, , lubbock, , 79423 Download at Boykma.Com Chapter 3 [ 73 ] When you rst start out, you can let Essbase automatically congure the Dense and Sparse dimension settings in your database. You do this using the EAS Outline Properties tab. Essbase will do this fairly well initially, based on the data already existing in the database. Notice in the preceding screenshot that there is an Auto congure option on the outline properties screen. If set to true, this option will let Essbase automatically set the Dense/Sparse settings of the dimensions in your database. As time goes on and as both your knowledge of your system's data grows and your experience with Essbase increases, you will nd that you can usually do a better job of conguring the Dense and Sparse settings yourself rather than let Essbase handle it. You can, at any time, change the Dense and Sparse attribute of any dimension. You will do this using the EAS at the database properties screen. One of the best features of Essbase is the outline or database restructure. Anytime you make a change to the database outline, you are offered the choice of saving the changes when you attempt to close the outline. The restructure choices available are Outline Only and Outline and Data. This material is copyright and is licensed for the sole use by Paul Corcorran on 5th July 2009 8601 ave. p #1, , lubbock, , 79423 Download at Boykma.Com Building the Essbase Outline [ 74 ] When you make changes to your database outline, the changes may also affect the way the data itself is stored. Changes such as moving a member or changing a Dense setting to a Sparse setting will always require you to perform an Outline and Data restructure. When the restructure is called for, Essbase will actually perform what could be best compared to in the relational world as database reorganization. All of the existing data is unloaded and then reloaded into a structure that is most efcient for the new database outline conguration and settings. When Essbase is performing an Outline Only database restructure, the database page les are not touched as only the database outline le is reorganized and resaved. An Outline Only restructure is triggered by making simple changes to the database, including adding or updating an alias table or adding or updating a member property. When Essbase deems it necessary to restructure the entire database, it will completely rebuild the database's page and index les. This type of database restructure is sometimes referred to as a Dense restructure. What triggers a Dense restructure is actually moving around the members in the database outline, adding new members to the outline, or changing the Dense and Sparse setting on a dimension. Very Important When performing a database restructure, Essbase actually rebuilds new temporary database page les from the existing page les. When nished, Essbase will delete the old page les and rename the new ones. Prior to any database restructure always make sure you have extra storage on your server. If the database you are restructuring is 30GB and you only have 20GB of space available Essbase will keep on going with the restructure until the disc space runs out and crashes the server! VEHICLES M A R K E T S CALENDAR PERIODS This material is copyright and is licensed for the sole use by Paul Corcorran on 5th July 2009 8601 ave. p #1, , lubbock, , 79423 Download at Boykma.Com . sole use by Paul Corcorran on 5th July 20 09 8601 ave. p #1, , lubbock, , 794 23 Download at Boykma.Com Chapter 3 [ 73 ] When you rst start out, you can let Essbase automatically congure the Dense. licensed for the sole use by Paul Corcorran on 5th July 20 09 8601 ave. p #1, , lubbock, , 794 23 Download at Boykma.Com Building the Essbase Outline [ 74 ] When you make changes to your database. earlier versions of Essbase so you would have needed to code your own functionality. This material is copyright and is licensed for the sole use by Paul Corcorran on 5th July 20 09 8601 ave. p #1,