Index

dkQueryableCollection

Purpose:

A queryable collection is a subclass of both query evaluator and sequential collection classes, therefore it can evaluate queries on its members. It can be used to store the result or scope of a query, which in turn can be queried further. For example, the result of dkDatastore :: evaluate() method is a dkQueryableCollection object which also implements the evaluate() method, so it can evaluate a query using its current collection members as the scope.

Class summary:

class dkQueryableCollection: public DKSequentialCollection, 
public dkQueryEvaluator
{
public:
 
   dkQueryableCollection(const dkDatastore& ds);
   virtual dkQueryableCollection();
 
   virtual dkIterator *createIterator() const;
 
   virtual DKAny  evaluate(const char  *query,
                           const short  ql_type,
                           const DKNVPair *params = 0) = 0;
};

Members:

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