Abstract: Recently,the eXtensibleMark-up Language (XML) has become a popular medium for data exchange or storage.Therefore,keyword search on XML documents has become one of the important researches.To speed up query on large amount of data,one of the most efficient methods is to build a good index.Although the method  Labeling Scheme for Dynamic XML data (LSDX)  can dynamically add new labels without reconstructing the index structure or updating existing old labels,there are two defects in LSDX which affect the practicality of LSDX.Accordingly,this article proposes  two label coding rules to completely solve the two defects of LSDX.

Key words: XML, DTD, indexing, labeling