| Summary: | 碩士 === 國立交通大學 === 資訊科學學系 === 82 === Signature file is a popular strategy applied to the text
retrieval methods of relational database. Recently, some
researches discovered that the characteristic of signature
file could deal with some problems of object-oriented
database. There are two primary parts in this thesis. Firstly,
it proposes a new method of signature file. Secondly,
signature file is applied to object - oriented database. Part
I : There are two factors that influence the efficiency of
the signature file. One is the false drop probability, the
other is the cost of searching the signature file. The
false drop probability is affected by the signature extraction
methods, while the cost of the signature file is decided by
searching storage structures. These two factors were
considered separately in the literature. In this thesis, the
signature extraction methods are integrated with the storage
structures to result in several new signature file methods.
The new methods take the two factors into
considerations at the same time. The new signature file
methods designed upon this concept have the
capabilities of high filtering and fast searching. Part II: In
the past, the index of OODB was designed for special queries.
It is inconvenient and not general. In this thesis, a new
method based on the signature file approach is proposed to
solve the problem of index in OODB.
|
|---|
