We propose a label based technique for an effective management of structural locks in XML databases. In particular we consider two types of such locks, acquired by transactions on sets of nodes. These are path locks and range locks – the latter understood as some subset of document's nodes defined by a pair of labels, with the sub-tree lock being a special case of range lock. We put forward algorithms for consolidation of shared locks that define a continuous covering, a way of initial processing simplifying and accelerating the lock manager. Two algorithms for the lock manager are framed with the use of XML labels for both the 2PL protocol and the cooperative one. We also point to some interesting ties between the lock management and the shortest path problem. Our motivation is given in the context of the SEDNA native XML DB isolation rules, however, our technique is useful for most of the fine-granular lock protocols.
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