Interface AccessPath

  • All Known Implementing Classes:
    AccessPathImpl

    public interface AccessPath
    AccessPath represents a proposed access path for an Optimizable. An Optimizable may have more than one proposed AccessPath.
    • Method Detail

      • setConglomerateDescriptor

        void setConglomerateDescriptor​(ConglomerateDescriptor cd)
        Set the conglomerate descriptor for this access path.
        Parameters:
        cd - A ConglomerateDescriptor
      • getConglomerateDescriptor

        ConglomerateDescriptor getConglomerateDescriptor()
        Get whatever was last set as the conglomerate descriptor. Returns null if nothing was set since the last call to startOptimizing()
      • setCostEstimate

        void setCostEstimate​(CostEstimate costEstimate)
        Set the given cost estimate in this AccessPath. Generally, this will be the CostEstimate for the plan currently under consideration.
      • getCostEstimate

        CostEstimate getCostEstimate()
        Get the cost estimate for this AccessPath. This is the last one set by setCostEstimate.
      • setCoveringIndexScan

        void setCoveringIndexScan​(boolean coveringIndexScan)
        Set whether or not to consider a covering index scan on the optimizable.
      • getCoveringIndexScan

        boolean getCoveringIndexScan()
        Return whether or not the optimizer is considering a covering index scan on this AccessPath.
        Returns:
        boolean Whether or not the optimizer chose a covering index scan.
      • setNonMatchingIndexScan

        void setNonMatchingIndexScan​(boolean nonMatchingIndexScan)
        Set whether or not to consider a non-matching index scan on this AccessPath.
      • getNonMatchingIndexScan

        boolean getNonMatchingIndexScan()
        Return whether or not the optimizer is considering a non-matching index scan on this AccessPath. We expect to call this during generation, after access path selection is complete.
        Returns:
        boolean Whether or not the optimizer is considering a non-matching index scan.
      • setJoinStrategy

        void setJoinStrategy​(JoinStrategy joinStrategy)
        Remember the given join strategy
        Parameters:
        joinStrategy - The best join strategy
      • getJoinStrategy

        JoinStrategy getJoinStrategy()
        Get the join strategy, as set by setJoinStrategy().
      • setLockMode

        void setLockMode​(int lockMode)
        Set the lock mode
      • getLockMode

        int getLockMode()
        Get the lock mode, as last set in setLockMode().
      • copy

        void copy​(AccessPath copyFrom)
        Copy all information from the given AccessPath to this one.
      • getOptimizer

        Optimizer getOptimizer()
        Get the optimizer associated with this access path.
        Returns:
        The optimizer associated with this access path.
      • initializeAccessPathName

        void initializeAccessPathName​(DataDictionary dd,
                                      TableDescriptor td)
                               throws StandardException
        Sets the "name" of the access path. if the access path represents an index then set the name to the name of the index. if it is an index created for a constraint, use the constraint name. This is called only for base tables.
        Parameters:
        td - TableDescriptor of the base table.
        dd - Datadictionary.
        Throws:
        StandardException - on error.