%iFind.Find.Abstract

At minimum, must support IsElement(). Return 1 if given e is in the set

Note that it's OK for the returned bitmap b to have no bits set to 1, including b="" . On the other hand, it's also OK for the method to skip such a chunk and proceed to the next c . We might also need:

The above methods are used to emulate regular sets and bitmaps. To emulate additional bitmap-specific behavior, the following 4 methods are needed. These methods follow the same convention used for SQL bitmap index structures. The chunk# .c is input/output, also proceeding in order starting and ending with "" . When the returned .c is non-NULL, then the actual bitmap chunk of bits is returned in .b : Method NextChunk(pChunk As %Integer = "", ByRef bits As %Binary) As %Integer

Method NextChunkInclusive(pChunk As %Integer = "", ByRef bits As %Binary) As %Integer

The following 4 methods, esp. the first 2, are needed to emulate a regular index. The element .e is an input/output parameter, iterating in a sequence through all the elements of following the normal subscript order ( "]]" ), starting and ending with "", similar to $ORDER():

Method PreviousChunk(pChunk As %Integer = "", ByRef bits As %Binary) As %Integer

Method PreviousChunkInclusive(pChunk As %Integer = "", ByRef bits As %Binary) As %Integer

Inherited description:

The NextItem(), NextItemInclusive(), PreviousItem(), and PreviousItemInclusive() methods are required when %INSUB is used.

For a given pItem, return the first item < pItem