P. Case Enhancing XML search with

XPath

2.0

Full-Text

&

P.

Case

Powerful

queries

of

character

strings,

numbers,

dates,

and

nodes

are

familiar

to

users

of

relational

database

systems.

Full-text

database

search

systems

feature

queries

that

(1)

use

logical,

proximity,

and

starts-with

operators,

(2)

offer

user

control

of

case

and

diacritics,

stemming,

and

wildcards,

and

(3)

support

thesauruses,

taxonomies,

and

ontologies.

Two

emerging

standards,

XQuery

1.0

and

XQ/XPFT

(XQuery

1.0

and

XPath

2.0

Full-Text),

combine

the

search

capabilities

of

the

aforementioned

systems

and

promise

to

change

the

face

of

full-text

searching.

This

paper

explores

the

expected

benefits

of

these

standards

in

searching

relational

data

and

full-text

documents

in

XML

from

an

end

user

point

of

view

and

describes

how

these

benefits

would

apply

to

a

search

system

used

at

the

Library

of

Congress.

These

standards

have

the

potential

to

solve

many

real-life

full-text

search

system

problems

and

to

restore

the

end-user

control

necessary

to

enable

and

facilitate

complex

searching.

INTRODUCTION

XML

promises

many

things

to

many

people.

Some

expect

XML

to

create

state-of-the-art

tools

for

document

composition.

Others

expect

it

to

enable

the

production

of

multiple

displays

from

a

single

source

document.

Still

others

expect

it

to

facilitate

the

interchange

of

data

and

documents

through

Web

services.

For

full-text

searching,

the

promise

lies

in

search

systems

that

are

more

powerful

and

com-

posable

(i.e.,

have

components

that

can

be

selected

and

assembled

in

various

combinations).

Two

forthcoming

standards

from

the

World

Wide

Web

Consortium

(W3C**),

XQuery

1

and

XQuery

and

XPath

Full-Text

2

(XQ/XPFT),

may

represent

the

first

steps

in

merging

and

improving

search

technologies

for

relational

databases

and

full-text

documents.

Once

relational

data

and

full-text

documents

are

both

stored

in

XML,

end

users

can

profit

from

being

able

to

search

them

together

with

a

single

search

engine,

exploiting

the

power

of

both

relational

database

querying

and

full-text

searching.

Currently,

more

and

more

full-text

search

function-

ality

is

being

exercised

by

the

use

of

scoring

and

categorization

algorithms.

Scoring

algorithms

pro-

duce

scores

for

search

results

that

predict

the

Ó

Copyright

2006

by

International

Business

Machines

Corporation.

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in

printed

form

for

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use

is

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royalty

provided

that

(1)

each

reproduction

is

done

without

alteration

and

(2)

the

Journal

reference

and

IBM

copyright

notice

are

included

on

the

first

page.

The

title

and

abstract,

but

no

other

portions,

of

this

paper

may

be

copied

or

distributed

royalty

free

without

further

permission

by

computer-based

and

other

information-service

systems.

Permission

to

republish

any

other

portion

of

the

paper

must

be

obtained

from

the

Editor.

0018-8670/06/$5.00

Ó

2006

IBM

IBM

SYSTEMS

JOURNAL,

VOL

45,

NO

2,

2006

CASE

353