一、普通查询
这是OracleText比较普遍且常用的应用场景。创建OracleText中Context类型的索引，生成大量的关键词，用于加快类似于普通的like ‘%xx%’操作速度，或者查询一些比较大的文档。可以使用contains函数进行数据检索。缺点：比较依赖于关键词和文档格式。有时可能不太准确。
以下为简单示例，这里不必多说，只是简单查询场景：
1.创建表
create table normal_context( id number , contentclob ) ;
2.初始化数据
insert into normal_context values(1 , ' Use thisindex to build a
textretrieval application
when your text consists
of largecoherent
documents.You can
indexdocuments of
differentformats such as
MS Word, HTMLor
plain text.
You cancustomize the
index in avariety of
ways.
This index typerequires
CTX_DDL.SYNC_INDEX
after DML onbase table.') ;
insert into normal_context values(2 ,'Use thisindex type for
better mixed query
performance.Typically,
with this indextype,
you index small
documents ortext
fragments.Other
columns in thebase
table, such asitem
names, prices,and
descriptionscan be
included in the indexto
improve mixedquery
performance.
This index typeis
transactional,
automaticallyupdating
itself afterDML to base
table. No CTX_
DDL.SYNC_INDEXis
necessary.') ;
insert into normal_context values(3 , ' UseCTXRULEindex to
build adocument
classification or routing
application.This index
is created on a table of
queries,where the
queriesdefine the
classification or routing
criteria.') ;
insert into normal_context values(4 , ' Createthis index when
you need tospeed up
existsNode()queries
on anXMLTypecolumn.') ;