zht32tris， zht16mswin950，zht16hkscs，utf8
--建立chinese lexer
Begin
ctx_ddl.create_preference(my_chinese_vgram_lexer, chinese_vgram_lexer);
ctx_ddl.create_preference(my_chinese_lexer, chinese_lexer);
End;
-- chinese_vgram_lexer
Create index ind_m_lex1 on my_lex(docs) indextype is ctxsys.context Parameters (lexer foo.my_chinese_vgram_lexer);
Select * from my_lex t where contains(docs, 中国) > 0;
-- chinese_lexer
drop index ind_m_lex1 force;
Create index ind_m_lex2 on my_lex(docs) indextype is ctxsys.context
Parameters (lexer ctxsys.my_chinese_lexer);
Select * from my_lex t where contains(docs, 中国) > 0;
3.3.4 User_lexer
Use USER_LEXER to plug in your own language-specific lexing solution. This enables you to
define lexers for languages that are not supported by Oracle Text. It also enables you to define a
new lexer for a language that is supported but whose lexer is inappropriate for your application.
3.3.5 Default_lexer
如果数据库在建立的时候指定的是中文则default_lexer 为chinese_vgram_lexer，如果是英文，则default_lexer 为basic_lexer
3.3.6 Query_procedure
This callback stored procedure is called by Oracle Text as needed to tokenize words in the query.
A space-delimited group of characters (excluding the query operators) in the query will be
identified by Oracle Text as a word.
3.3.7 参考脚本
--建立basic_lexer
begin
ctx_ddl.create_preference(mylex, BASIC_LEXER);
ctx_ddl.set_attribute (mylex, printjoins, _-); --保留_ -符号
ctx_ddl.set_attribute (mylex,mixed_case,yes); --区分大小写
end;
create index indx_m_lex on my_lex(docs) indextype is ctxsys.context parameters(lexer
mylex);
--建立 chinese_vgram_lexer 或是chinese_lexer
Begin
ctx_ddl.create_preference(my_chinese_vgram_lexer, chinese_vgram_lexer);
ctx_ddl.create_preference(my_chinese_lexer, chinese_lexer);
End;
-- chinese_vgram_lexer
Create index ind_m_lex1 on my_lex(docs) indextype is ctxsys.context
Parameters (lexer ctxsys.my_chinese_vgram_lexer);