Defining Semiadditive Behavior

Semiadditive measures, which do not uniformly aggregate across all dimensions, are very common in many business scenarios. Every cube that is based on snapshots of balances over time exhibits this problem. You can find these snapshots in applications dealing with securities, account balances, budgeting, human resources, insurance policies and claims, and many other business domains.

Add semiadditive behavior to a cube to define an aggregation method for individual measures or members of the account type attribute. If the cube contains an account dimension, you can automatically set semiadditive behavior based on the account type.

To add semiadditive behavior, you use the Business Intelligence Wizard, and select the Define semiadditive behavior option on the Choose Enhancement page. This wizard then guides you through the steps of identifying which measures have semiadditive behavior.

Define Semiadditive Behavior

On the Define Semiadditive Behavior page of the wizard, you select how to define semiadditivity by selecting one of the following options:

  • Turn off semiadditive behavior
    Removes semiadditive behavior from a cube in which semiadditive behavior was previously defined. This selection resets a measure to SUM if it is set to any of the following aggregation function types:

    • By Account

    • Average of Children

    • First Child

    • Last Child

    • Last Nonempty Child

    • First Nonempty Child

    • None

    This option does not change measures with a regular aggregation function: Sum, Min, Max, Count, or DistinctCount.

  • The wizard has detected the 'Account" account dimension, which contains semiadditive members. The server will aggregate members of this dimension according to the semiadditive behavior specified for each account type.
    Causes the system to set all measures from a measure group dimensioned by an Account type dimension to the By Account aggregation function and the server will aggregate members of the dimension according to the semiadditive behavior specified for each account type.

    Note

    This option is selected by default if the wizard detects an Account type dimension.

  • Define semiadditive behavior for individual measures
    Selects the semiadditive behavior of each measure individually. The default setting is SUM (fully additive).

    Note

    This option is selected by default if the wizard does not detect an Account type dimension.

    For each measure, you can select from the types of semiadditive functionality described in the following table.

    Semiadditive function

    Description

    Average of Children

    The aggregation of a member is the average of its children.

    ByAccount

    The system reads the semiadditive behavior specified for the account type.

    Count

    The aggregation is a count of members.

    Distinct Count

    The aggregation is a count of unique members.

    First Child

    The member value is evaluated as the value of its first child along the time dimension.

    FirstNonEmpty

    The member value is evaluated as the value of its first child along the time dimension that contains data.

    LastChild

    The member value is evaluated as the value of its last child along the time dimension.

    LastNonEmpty

    The member value is evaluated as the value of its last child along the time dimension that contains data.

    Max

    The standard maximum aggregation function is applied.

    Min

    The standard minimum aggregation function is applied.

    None

    No aggregation is applied.

    Sum

    The standard summation function is applied.

Any existing semiadditive behavior is overwritten when you complete the wizard.

See Also

Concepts