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Description

Edit keys at this level only

= In-memory indexing of data is done 'behind-the-scenes' by some classes implementing -IP-.0x000D0x000A0x000D0x000AOne such class included in -ARCCore- is -PCollection-0x000D0x000Awhich uses -Indexing- for all keys ending with 'Id' (keys assumed to be foreign keys).0x000D0x000A0x000D0x000AThis class is useful as container for a collection of entities (a table in RBDMS-terms).0x000D0x000A0x000D0x000AMethods in -IP- which should be used if indexing is assumed to be necessary, is:0x000D0x000A-TrySetPP-: SetPP = set property of property. Sets property of entity contained within this class0x000D0x000A-GetKeysEqualToValue-: Returns properties which themselves again have key and value equal to the given key and value.0x000D0x000ANote that these are default interface methods, that is, the default implementation does not support indexing.0x000D0x000A0x000D0x000A-TryStore- will look for classes called '0x007BEntityType0x007DCollection' to instantiate as containers for collections of entities (classes with such names are assumed to be suitable for that purpose).0x000D0x000AExample: If the application has a type 'Order', then a class called 'OrderCollection' (if found) will be used as storage container for the collection of 'Order' objects (if not the 'ordinary' -PRich- will be used).0x000D0x000A0x000D0x000ASuch a class can be created just by the following code:0x000D0x000A  public class OrderCollection : PCollection 0x007B0x000D0x000A  0x007D0x000D0x000A0x000D0x000AIn this manner, indexing will be ensured for foreign keys like CustomerId, EmployeeId, ShipperId and so on.0x000D0x000A0x000D0x000ANote that other -ApplicationSpecificCode- implementations does not necessarily have to inherit -PCollection- but they should implemented interfaces like -IGetKeysEqualToValue- in order to clearly state that they support indexing.0x000D0x000A0x000D0x000AIndexing will use more memory but is often necessary for big collections when querying across collections of entities (querying across tables).0x000D0x000A0x000D0x000ASee also -MemoryConsumption-.0x000D0x000A

Edit keys at all sub levels.
NOTE: Edits are always additive. Use 'Invalid' in order to delete keys.

Generated 2025-11-04 18:18:31.112 UTC