4). Combining keyword search and form for adhoc querying of db, E.chu,A.Baid,X.chai
A. Doan and J.F. Naughton:
- Automatically generate a lot of query form in advance.
- User input several keyword to find relevent query form.
- It works well in db have rich textual information.
- Here query rewrite by mapping data value to schema value
during keyword search.
- Display the returned form as a flat list.
DISADVANTAGE
It is not appropriate when user does not have a concrete keyword
to describe query at the begining, especially for numeric attributes.
Given a keyword query, augment user queries with form terms.
Form terms such as schema, terms,SQL, Keywords & Natural language
description.
Retrive form that containing form term.
To implement this, use two inverted indexes: one for data set
other for set of forms.
The first index is called Data index,takes in a term and return a set of
< tuple_id, table> pair.
tuple id is the primary key of tuple.
table is the name of the table containing the tuple.
Second index called Form index.
It returns form id.
Here use DOUBLE- INDEX OR approach.Include two step.
First step is query rewrite.
Second step is simply prob Form index with terms in FormTerms.
It also uses DOUBLE-INDEX AND approach.
This generate new queries by taking term from each bucket of
FormTerm.Then evaluate query with semantic AND, then union result.
DOUBLE-INDEX JOIN approach, estimate "dead forms" with extra probe to DataIndex.
Rank according to user interest.
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