Class MBtreeKey

MBtreeKey

Support

Supported from 5.0

Description

Interface for ordering and creating keys for entries in a B-tree.

Derived classes implement this interface for particular types of key.

Defined in MBtreeKey:
Between(), Compare(), Key()

virtual void Between(const TAny* aLeft,const TAny* aRight,TBtreePivot& aPivot) const=0;

Description

Gets the midpoint between two keys.

The generated midpoint will be greater or equal to aLeft (by a comparison performed by the Compare() function), and less than aRight.

Parameters

const TAny* aLeft First key const TAny* aRight Second key TBtreePivot& aPivot On return, the midpoint between the two keys

virtual TInt Compare(const TAny* aLeft,const TAny* aRight) const=0;

Description

Orders two keys.

Parameters

const TAny* aLeft Pointer to first key const TAny* aRight Pointer to second key

Return value

TInt Positive, if the first key is after the second key; negative, if the first key is before the second key; zero, if the keys are equal

virtual const TAny* Key(const TAny* anEntry) const;

Description

Gets the key value for an entry.

Parameters

const TAny* anEntry Object for which to get the key value

Return value

const TAny* Pointer to the key value