Specifies the seed for a repeatable holdout partition that contains the test set of a MiningStructure element. This seed ensures that the model content remains the same during reprocessing. If unspecified or set to 0, Analysis Services creates a seed by using a hashing algorithm on the name of the mining structure.
When you first create a mining structure, the ID and the name are the same. However, you can change the name of the mining structure. Therefore, if you want to ensure that the partition is repeatable, you should not rely on the seed created by the name, but should explicitly set a seed.
Additionally, when you create a copy of a mining structure by using the EXPORT statement, Analysis Services will retain the name for the new mining structure but will automatically generate a new ID. Therefore, it is possible to have two mining structures that share the same name but have different IDs. Any two mining structures that have the same name will have the same seed. However, as the partitioning of the data also depends on the source data, the actual contents of the partitions in each structure may be different.
The new properties HoldoutMaxCases, HoldoutMaxPercent, HoldoutSeed, or HoldoutActualSize are available only in SQL Server 2008. Therefore, you must prefix these properties with the new namespace as shown in the syntax description, or Analysis Services will return an error.
Note In SQL Server 2005, Analysis Services did not support the use of holdout partitions on a mining structure. Therefore, Analysis Services Scripting Language (ASSL) statements that contain the holdout parameters HoldoutMaxCases, HoldoutMaxPercent, HoldoutSeed, or HoldoutActualSize cannot be used in SQL Server 2005. If you use one of these holdout parameters in an ASSL statement in SQL Server 2005, Analysis Services will return an error.
The element that corresponds to the parent of HoldoutSeed in the Analysis Management Objects (AMO) object model is MiningStructure.