## Defining Calculation Order

The information in this chapter applies only to block storage databases and is not relevant to aggregate storage databases.

Also see:

## Data Storage in Data Blocks

Essbase stores data values in data blocks. Essbase creates a data block for each unique combination of sparse dimension members (providing that at least one data value exists for the combination).

Each data block contains all the dense dimension member values for its unique combination of sparse dimension members.

In the Sample.Basic database, the Year, Measures, and Scenario dimensions are dense; the Product and Market dimensions are sparse:

Figure 117. Dimensions from the Sample.Basic Database Note:

Sample.Basic also contains five attribute dimensions. These dimensions are sparse, Dynamic Calc, meaning that attribute data is not stored in the database. See Working with Attributes.

Essbase creates a data block for each unique combination of members in the Product and Market dimensions (providing that at least one data value exists for the combination). For example, it creates one data block for the combination of 100-10, New York. This data block contains all the Year, Measures, and Scenario values for 100-10, New York.

Figure 118. Product and Market Dimensions from the Sample.Basic Database In Essbase, member combinations are denoted by the cross-dimensional operator. The symbol for the cross-dimensional operator is -> (a hyphen followed by a greater-than symbol). So 100-10, New York is written 100-10 -> New York.

You can categorize data blocks in the following ways:

• Input

These blocks are created by loading data to cells in a block. Input blocks can be created for (1) sparse, level 0 member combinations or (2) sparse, upper-level member combinations, when at least one of the sparse members is a parent-level member. Input blocks can be level 0 or upper-level blocks.

• Noninput

These blocks are created through calculations. For example, in Sample.Basic, the East -> Cola block is created during a sparse calculation process (that is, the block did not exist before calculation).

• Level 0

These blocks are created for sparse member combinations when all of the sparse members are level 0 members. For example, in Sample.Basic, New York -> Cola is a level 0 block because New York and Cola are level 0 members of their respective sparse dimensions. Level 0 blocks can be input or noninput blocks; for example, a level 0 noninput block is created during an allocation process, where data is loaded at a parent level and then allocated down to level 0.

• Upper level

These blocks are created for sparse member combinations when at least one of the sparse members is a parent-level member. Upper-level blocks can be input or noninput blocks.

## Member Calculation Order

Essbase calculates a database at the data block level, bringing one or more blocks into memory and calculating the required values within the block. Essbase calculates the blocks in order, according to their block numbers. The database outline tells Essbase how to order the blocks. Within each block, Essbase calculates the values in order according to the hierarchy in the database outline. Therefore, overall, Essbase calculates a database based on the database outline.

When you perform a default calculation (CALC ALL) on a database, Essbase calculates the dimensions in this order:

• If both a dimension tagged as accounts and a dimension tagged as time exist, and if formulas are applied to members on the accounts dimension, Essbase calculates in this order:

1. Dimension tagged as accounts

2. Dimension tagged as time

3. Other dense dimensions (in the order in which they are displayed in the database outline)

4. Other sparse dimensions (in the order in which they are displayed in the database outline)

• Otherwise, Essbase calculates in this order:

1. Dense dimensions (in the order in which they are displayed in the database outline)

2. Sparse dimensions (in the order in which they are displayed in the database outline)

Note:

Attribute dimensions, which are not included in the database consolidation, do not affect calculation order. See Working with Attributes.

In the Sample.Basic database, the dimensions are calculated in this order: Measures, Year, Scenario, Product, and Market.

You can override the default order by using a calculation script. See Developing Calculation Scripts.

## Understanding the Effects of Member Relationships

The order of calculation within each dimension depends on the relationships between members in the database outline. Within each branch of a dimension, level 0 values are calculated first followed by their level 1, parent value. Then the level 0 values of the next branch are calculated, followed by their level 1, parent value. The calculation continues in this way until all levels are calculated.

Figure 119, Year Dimension from the Sample.Basic Database shows the Year dimension from the Sample.Basic database. The calculation order is shown on the left. This example assumes that the parent members are not tagged as Dynamic Calc. See Dynamically Calculating Data Values.

Figure 119. Year Dimension from the Sample.Basic Database Jan is the first member in the first branch. Jan has no formula, so it is not calculated. The same applies to Feb and Mar, the other two members in the branch.

Essbase calculates Qtr1 by consolidating Jan, Feb, and Mar. In this example, these members are added.

Essbase then calculates the Qtr2 through Qtr4 branches in the same way.

Finally, Essbase calculates the Year member by consolidating the values of Qtr1 through Qtr4. These members are added.

## Determining Member Consolidation

You can choose how Essbase consolidates members by applying any calculation operator (+, -, /, *, %, ~, ^) to the members in the database outline.

If an accounts member has a time balance tag (First, Last, or Average), Essbase consolidates it accordingly. See Calculating First, Last, and Average Values.

If a parent member has a label only tag, Essbase does not calculate the parent from its children.

If a member has a ~ tag, Essbase does not consolidate the member up to its parent.

If a member has a ^ tag, Essbase does not consolidate the member in any dimension.

Note:

If you use dynamic calculations, Essbase may use a different calculation order. See Calculation Order for Dynamic Calculation.

## Ordering Dimensions in the Database Outline

To ensure the required calculation results, consider the calculation order of the dimensions in the database outline if you do either of these tasks:

• Use calculation operators to divide (/), multiply (*), or calculate percentages (%) for members in the database outline.

• Place formulas on members in the database outline.

You need not consider calculation order if you use only calculation operators to add (+) and subtract (–) members in the database outline and you do not use formulas in the outline.

## Placing Formulas on Members in the Database Outline

If you place formulas on members in the database outline, consider the calculation order of the dimensions. A formula that is attached to a member on one dimension may be overwritten by a subsequent calculation on another dimension.

For example, the Sample.Basic database has a Measures dimension, tagged as accounts, and a Year dimension, tagged as time. Measures is calculated first and Year second. If you attach a formula to Margin on the Measures dimension, Essbase calculates the formula when it calculates the Measures dimension. Essbase then overwrites the formula when it consolidates the Year dimension. See Cell Calculation Order.

## Using the Calculation Operators *, /, and %

If you use calculation operators to multiply ( * ), divide ( / ), and calculate percentages ( % ) for members in the database outline, consider the calculation order of the dimensions. The required calculated values may be overwritten by a subsequent calculation on another dimension.

For example, the Sample.Basic database has a Measures dimension, tagged as accounts, and a Year dimension, tagged as time. Measures is calculated first and Year second. If you multiply members on the Measures dimension, the calculated results may be overwritten when Essbase consolidates values on the Year dimension. See Cell Calculation Order.

When you use a multiplication ( * ), division ( / ), or percentage ( % ) operator to consolidate members, carefully order the members in the branch to achieve the required result.

Figure 120. Calculation Operators in the Database Outline In Figure 120, Calculation Operators in the Database Outline, assume that the user wants to divide the total of Child 2 and Child 3 by Child 1. However, if Child 1 is the first member, Essbase starts with Child 1, starting with the value #MISSING, and dividing it by Child 1. The result is #MISSING. Essbase then adds Child 2 and Child 3. Obviously, this result is not the required one.

To calculate the correct result, make Child 1 the last member in the branch.

You can apply a formula to a member on the database outline to achieve the same result. However, it is far more efficient to use these calculation operators on members as shown in Figure 120, Calculation Operators in the Database Outline.

## Avoiding Forward Calculation References

To obtain the calculation results you expect, ensure that the outline does not contain forward calculation references. Forward calculation references occur when the value of a calculating member is dependent on a member that Essbase has not yet calculated. In these cases, Essbase may not produce the required calculation results.

For example, consider this Product dimension:

Figure 121. Example Product Dimension This Product dimension has three forward calculation references. Two shared members and one nonshared member have forward calculation references, as shown in Figure 122, Example Product Dimension Showing Forward Calculation References:

Figure 122. Example Product Dimension Showing Forward Calculation References In Outline Editor, when you verify the outline, Essbase identifies shared members with forward calculation references. Verifying the outline does not identify nonshared members that have forward calculation references. You can save and use an outline containing forward calculation references. To verify the outline, see “Verifying Outlines” in the Oracle Essbase Administration Services Online Help.

Consider the five members under Diet. The members P100-20, P300-20, and P500-20 have forward calculation references:

• P100-20 (+) (Shared Member): Essbase calculates the shared member P100-20 before it calculates the actual member P100-20. Because the actual member P100-20 has children, Essbase must calculate the actual member by adding its children before it can accurately calculate the shared member P100-20.

• P300-20 (+) (Shared Member): Essbase calculates the shared member P300-20 before it calculates the actual member P300-20. Because the actual member P300-20 has a formula, Essbase must calculate the actual member before it can accurately calculate the shared member P300-20.

• P500-20 (+) (“P200-20” + “P300-20”): The formula applied to P500-20 references members that Essbase has not yet calculated. One referenced member, P300-20, has its own formula, and Essbase must calculate P300-20 before it can accurately calculate P500-20. The members P200-20 and P400-20 calculate correctly, because they do not have forward calculation references.

• P200-20 (+) (Shared Member): P200-20 is not a forward calculation reference, although Essbase calculates the shared member P200-20 before it calculates the actual member P200-20. The actual member P200-20 has no calculation dependencies (no children and no formula). Therefore, Essbase does not need to calculate the actual member before the shared member. Essbase simply takes the value of the actual member.

• P400-20 (+) (“P200-10” * 2): P400-20 is not a forward calculation reference, although the formula that is applied to P400-20 references a member that Essbase has not yet calculated. The member referenced in the formula does not itself have calculation dependencies. P200-10 is the only member in the formula, and P200-10 does not itself have children or a formula. Essbase accurately calculates P400-20.

To get accurate calculation results for P100-20, P300-20, and P500-20, change the order of members in the outline. By placing the Diet shared members after the Regular members, you ensure that Essbase calculates the members in the required order.

Figure 123. Changed Product Dimension Without Forward Calculation References Now Essbase calculates:

• The actual member P100-20 before it calculates the shared member P100-20. So, P100-20 no longer has a forward calculation reference.

• The actual member P300-20 before the shared member P300-20. So, P300-20 no longer has a forward calculation reference.

• The referenced member with a formula, P300-20, before the member P500-20. So, P500-20 no longer has a forward calculation reference.

## Block Calculation Order

Essbase calculates blocks in the order in which the blocks are numbered. Essbase takes the first sparse dimension in a database outline as a starting point. It defines the sparse member combinations from this first dimension.

In the Sample.Basic database, Product is the first sparse dimension in the database outline.

Figure 124. Dimensions in the Sample.Basic Database Note:

The attribute dimensions in the Sample.Basic outline (not shown in the figure above), are not included in the database consolidation and do not affect block calculation order. See Working with Attributes..

Product has 19 members (excluding the shared members, for which Essbase does not create data blocks). Therefore, the first 19 data blocks in the database are numbered according to the calculation order of members in the Product dimension.

Figure 125. Product Dimension from the Sample.Basic Database The other sparse dimension is Market. The first 19 data blocks contain the first member to be calculated in the Market dimension, which is New York.

The following table shows the sparse member combinations for the first five of these 19 data blocks:

Block Number

Product Member

Market Member

0

Cola (100-10)

New York

1

Diet Cola (100-20)

New York

2

Caffeine Free Cola (100-30)

New York

3

Colas (100)

New York

4

Old Fashioned (200-10)

New York

The next member in the Market dimension is Massachusetts. Essbase creates the next 19 data blocks for sparse combinations of each Product member and Massachusetts.

The following table shows the sparse member combinations for the block numbers 19 through 23:

Block Number

Product Member

Market Member

19

Cola (100-10)

Massachusetts

20

Diet Cola (100-20)

Massachusetts

21

Caffeine Free Cola (100-30)

Massachusetts

22

Colas (100)

Massachusetts

23

Old Fashioned (200-10)

Massachusetts

Essbase continues until blocks have been created for all combinations of sparse dimension members for which at least one data value exists.

Essbase creates a data block only if at least one value exists for the block. For example, if no data values exist for Old Fashioned Root Beer (200-10) in Massachusetts, then Essbase does not create a data block for 200-10 -> Massachusetts. However, Essbase does reserve the appropriate block number for 200-10 -> Massachusetts in case data is loaded for that member combination in the future.

When you run a default calculation (CALC ALL) on a database, each block is processed in order, according to its block number. If you have Intelligent Calculation turned on, and if the block does not need to be calculated, then Essbase skips the block and moves to the next block. For information about how intelligent calculation is used to optimize performance, see Understanding Intelligent Calculation.

## Data Block Renumbering

Essbase renumbers the data blocks when you make any of these changes:

• Move a sparse dimension

• Change a dense dimension to a sparse dimension

• Move any member in a sparse dimension

• Delete any member in a sparse dimension

• Add a member to a sparse dimension

## Cell Calculation Order

Each data block contains all the dense dimension member values for its unique combination of sparse dimension members. Each data value is contained in a cell of the data block.

The order in which Essbase calculates the cells within each block depends on how you have configured the database. How you have configured the database defines the member calculation order of dense dimension members within each block. It also defines the calculation order of blocks that represent sparse dimension members.

Use the following sections to better understand cell calculation order.

## Cell Calculation Order: Example 1

Consider the simplest case, in which both of these conditions are true:

• No dimensions have time or accounts tags.

• The setting for consolidating #MISSING values is turned on.

Market and Year are both dense dimensions. The following table shows a subset of the cells in a data block. Data values have been loaded into the input cells. Essbase calculates the shaded cells. The numbers in bold show the calculation order for these cells. The cell with multiple consolidation paths is darkly shaded. Essbase calculates dense dimensions in the order in which they display in the database outline. Assuming that the Year dimension is displayed before the Market dimension in the database outline, the Year dimension is calculated before the Market dimension.

The cells are calculated in this order:

1. Qtr1 -> New York

2. Qtr1 -> Massachusetts

3. Jan -> East

4. Feb -> East

5. Mar -> East

6. Qtr1 -> East

Qtr1 -> East has multiple consolidation paths. It can be consolidated on Market or on Year. When consolidated on Market, it is a consolidation of Qtr1 -> New York and Qtr1 -> Massachusetts. When consolidated on Year, it is a consolidation of Jan -> East, Feb -> East, and Mar -> East.

Essbase knows that Qtr1 -> East has multiple consolidation paths. Therefore, it calculates Qtr1 -> East only once and uses the consolidation path of the dimension calculated last. In the above example, this dimension is Market.

The results are shown in this table: Note:

Qtr1 -> East has been calculated only once by consolidating the values for Qtr1.

From the calculation order, you can see that if you place a member formula on Qtr1 in the database outline, Essbase ignores it when calculating Qtr1 -> East. If you place a member formula on East in the database outline, the formula is calculated when Essbase consolidates Qtr1 -> East on the Market consolidation path. If required, you can use a calculation script to calculate the dimensions in the order you choose. See Developing Calculation Scripts.

## Cell Calculation Order: Example 2

Consider a second case, in which both of these conditions are true:

• No dimensions have time or accounts tags.

• The setting for consolidating #MISSING values is turned off (the default).

Market and Year are both dense dimensions. The following table shows a subset of the cells in a data block. Data values have been loaded into the input cells. Essbase calculates the shaded cells. The numbers in bold show the calculation order for these cells. The cell with multiple consolidation paths is darkly shaded. Essbase calculates dense dimensions in the order in which they are defined in the database outline. Assuming that the Year dimension is positioned before the Market dimension in the database outline, the Year dimension is calculated before the Market dimension.

The cells are calculated in this order:

1. Qtr1 -> New York

2. Qtr1 -> Massachusetts

3. Qtr1 -> East

4. Jan -> East

5. Feb -> East

6. Mar -> East

7. Qtr1 -> East

Qtr1 -> East is calculated on both the Year and Market consolidation paths. First, it is calculated as a consolidation of Qtr1 -> New York and Qtr1 -> Massachusetts. Second, it is calculated as a consolidation of Jan -> East, Feb -> East, and Mar -> East.

The results are identical to the previous case. However, Qtr1 -> East has been calculated twice. This fact is significant when you need to load data at parent levels (see Cell Calculation Order: Example 3). From the calculation order, you can see that if you place a member formula on Qtr1 in the database outline, its result is overwritten when Essbase consolidates Qtr1 -> East on the Market consolidation path. If you place a member formula on East in the database outline, the result is retained, because the Market consolidation path is calculated last.

## Cell Calculation Order: Example 3

Consider the previous example, and add a third condition:

• No dimensions have time or accounts tags.

• The setting for consolidating #MISSING values is turned off (the default).

• Data values have been loaded at parent levels.

Market and Year are both dense dimensions. The following table shows a subset of the cells in a data block. Data values have been loaded into cells at the parent level.

Essbase calculates dense dimensions in the order in which they are defined in the database outline. Assuming that the Year dimension is positioned before the Market dimension in the database outline, the Year dimension is calculated before the Market dimension. The cells are calculated in the same order as in Example 2. Qtr1 -> East is calculated on both the Year and Market consolidation paths.

Because the setting for consolidating #MISSING values is turned off, Essbase does not consolidate the #MISSING values. Thus, the data that is loaded at parent levels is not overwritten by the #MISSING values below it.

However, if any of the child data values are not #MISSING, these values are consolidated and overwrite the parent values. For example, if Jan -> New York contains 50000.00, this value overwrites the values loaded at parent levels.

Essbase first correctly calculates the Qtr1 -> East cell by consolidating Jan -> East, Feb -> East, and Mar -> East. Second, it calculates on the Market consolidation path. However, it does not consolidate the #MISSING values in Qtr1 -> New York and Qtr1 -> Massachusetts, so the value in Qtr1 -> East is not overwritten.

This table shows the results: Essbase must calculate the Qtr1 -> East cell twice to ensure that a value is calculated for the cell. If Qtr1 -> East is calculated according to only the last consolidation path, the result is #MISSING, which is not the required result.

## Cell Calculation Order: Example 4

Consider a case in which all of these conditions are true:

• The Year dimension is tagged as time.

• The Measures dimension is tagged as accounts.

• The setting for consolidating #MISSING values is turned off (the default).

Figure 126, Profit Branch of the Measures Dimension in the Sample.Basic Database shows the Profit branch of the Measures dimension in the Sample.Basic database. This example assumes that Total Expenses is not a Dynamic Calc member. See Dynamically Calculating Data Values.

Figure 126. Profit Branch of the Measures Dimension in the Sample.Basic Database The following table shows a subset of the cells in a data block. Data values have been loaded into the input cells. Essbase calculates the shaded cells. The numbers in bold show the calculation order for these cells. Cells with multiple consolidation paths are darkly shaded.

The Marketing, Payroll, and Misc Expenses values have been loaded at the Qtr1, parent level. Essbase calculates a dimension tagged as accounts first, followed by a dimension tagged as time. Therefore, in the above example, Measures is calculated before Year.

Three cells have multiple consolidation paths:

• Margin -> Qtr1

• Total Expenses -> Qtr1

• Profit -> Qtr1

Because the setting for consolidating #MISSING values is turned off, Essbase does not consolidate the #MISSING values. Thus, any data that is loaded at parent levels is not overwritten by the #MISSING values and Essbase calculates the three cells with multiple consolidation paths twice.

The results are shown in this table: From the calculation order, you can see that if you place a member formula on, for example, Margin in the database outline, its result is overwritten by the consolidation on Qtr1.

## Cell Calculation Order for Formulas on a Dense Dimension

The cell calculation order within a data block is not affected by formulas on members. When Essbase encounters a formula in a data block, it locks any other required data blocks, calculates the formula, and proceeds with the data block calculation.

When placing a formula on a dense dimension member, carefully consider the cell calculation order. As described in the examples above, the dimension calculated last overwrites previous cell calculations for cells with multiple consolidation paths. If required, you can use a calculation script to change the order in which the dimensions are calculated. See Developing Calculation Scripts and Developing Formulas.

## Calculation Passes

Whenever possible, Essbase calculates a database in one calculation pass through the database. Thus, it reads each of the required data blocks into memory only once, performing all relevant calculations on the data block and saving it. However, in some situations, Essbase must perform more than one calculation pass through a database. On subsequent calculation passes, Essbase brings data blocks back into memory, performs further calculations on them, and saves them again.

When you perform a default, full calculation of a database (CALC ALL), Essbase attempts to calculate the database in one calculation pass. If you have dimensions that are tagged as accounts or time, Essbase may have to do more than one calculation pass through the database.

The following table shows the number of calculation passes Essbase performs if you have dimensions that are tagged as time or accounts, and you have at least one formula on the accounts dimension:

Dimension Tagged As:

Calculation Passes

During each calculation pass, Essbase calculates based on:

Accounts

Time

Dense or Sparse

None

1

All dimensions

Dense

Dense

1

All dimensions

Dense

Sparse

2

Pass 1: Accounts and time dimensions

Pass 2: Other dimensions

Sparse

Sparse

2

Pass 1: Accounts and time dimensions

Pass 2: Other dimensions

Sparse

Dense

2

Pass 1: Accounts dimension

Pass 2: Other dimensions

If you are using formulas that are tagged as Two-Pass, Essbase may need to do an extra calculation pass to calculate these formulas. See Using Two-Pass Calculation.

When you use a calculation script to calculate a database, the number of calculation passes Essbase needs to perform depends upon the calculation script. See Calculation Passes and Understanding Multiple-Pass Calculations. Also see Grouping Formulas and Calculations.

If the isolation level is set for committed access, and multiple passes are required, Essbase writes data values at the end of each pass. Data retrievals that occur between passes can pick up intermediate values.

When you calculate a database, Essbase automatically displays the calculation order of the dimensions for each pass through the database and tells you how many times Essbase has cycled through the database during the calculation. Essbase displays this information in the ESSCMD window and in the application log. To display the application log, see Viewing the Essbase Server and Application Logs.

For each data block, Essbase decides whether to do a dense or a sparse calculation. The type of calculation it chooses depends on the type of values within the data block. When you run a default calculation (CALC ALL) on a database, each block is processed in order, according to its block number.

Essbase calculates the blocks using this procedure:

• If you have Intelligent Calculation turned on, and if the block does not need to be calculated (if it is marked as clean), Essbase skips the block and moves to the next block. See Understanding Intelligent Calculation.

• If the block needs recalculating, Essbase checks to see if the block is a level 0, an input, or an upper-level block. See Data Storage in Data Blocks.

• If the block is a level 0 block or an input block, Essbase performs a dense calculation on the block. Each cell in the block is calculated. See Cell Calculation Order.

• If the block is an upper-level block, Essbase either consolidates the values or performs a sparse calculation on the data block.

The sparse member combination of each upper-level block contains at least one parent member. Essbase consolidates or calculates the block based on the parent member’s dimension. For example, if the upper-level block is for Product -> Florida from the Sample.Basic database, then Essbase chooses the Product dimension.

If the sparse member combination for the block has more than one parent member, Essbase chooses the last dimension in the calculation order that includes a parent member. For example, if the block is for Product -> East, and you perform a default calculation on the Sample.Basic database, Essbase chooses the Market dimension, which contains East. The Market dimension is last in the default calculation order because it is placed after the Product dimension in the database outline. See Member Calculation Order.

Based on the chosen sparse dimension, Essbase either consolidates the values or performs a sparse calculation on the data block:

• If a formula is applied to the data block member on the chosen sparse dimension, Essbase performs a formula calculation on the sparse dimension. Essbase evaluates each cell in the data block. The formula affects only the member on the sparse dimension, so overall calculation performance is not significantly affected.

• If the chosen sparse dimension is a default consolidation, Essbase consolidates the values, taking the values of the previously calculated child data blocks.

## Calculation of Shared Members

Shared members are those that share data values with other members. For example, in the Sample.Basic database, Diet Cola, Diet Root Beer, and Diet Cream are consolidated under two parents: under Diet and under their product types—Colas, Root Beer, and Cream Soda.

Figure 127. Calculating Shared Members The members under the Diet parent are shared members. See Understanding Shared Members.

A calculation on a shared member is a calculation on the actual member. If you use the FIX command to calculate a subset of a database and the subset includes a shared member, Essbase calculates the actual member.