-- -- Copyright (C) 2001, 2002 MIT -- -- This file is part of dotLRN. -- -- dotLRN is free software; you can redistribute it and/or modify it under the -- terms of the GNU General Public License as published by the Free Software -- Foundation; either version 2 of the License, or (at your option) any later -- version. -- -- dotLRN is distributed in the hope that it will be useful, but WITHOUT ANY -- WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS -- FOR A PARTICULAR PURPOSE. See the GNU General Public License for more -- details. -- -- -- Support for searching of forum messages -- -- @author yon@openforce.net -- @creation-date 2002-07-01 -- @version $Id: forums-search-create.sql,v 1.5 2002/08/09 20:51:49 yon Exp $ -- -- IMPORTANT: -- replace all instances of the string "yon" below this line with your schema -- user and schema password accordingly. also, replace the "connect -- ctxsys/ctxsys" statement with the appropriate values for your system. need -- to figure out how to do this in a better way. -- as normal user create or replace procedure index_message ( rid in rowid, tlob in out NOCOPY clob ) is offset number := 1; begin for row in (select forums_messages.subject, forums_messages.content, persons.first_names, persons.last_name from forums_messages, persons where forums_messages.rowid = rid and forums_messages.user_id = persons.person_id) loop dbms_lob.writeappend(tlob, length(row.subject) + 1, ' ' || row.subject); dbms_lob.append(tlob, row.content); dbms_lob.writeappend(tlob, length(row.first_names) + 1, ' ' || row.first_names); dbms_lob.writeappend(tlob, length(row.last_name) + 1, ' ' || row.last_name); end loop; end; / show errors -- as ctxsys connect ctxsys/ctxsys; create or replace procedure s_index_message ( rid in rowid, tlob in out NOCOPY clob ) is begin yon.index_message(rid, tlob); end; / show errors grant execute on s_index_message to yon; grant execute on ctx_ddl to yon; -- as normal user connect yon/yon; execute ctx_ddl.create_preference('forums_user_datastore', 'user_datastore'); execute ctx_ddl.set_attribute('forums_user_datastore', 'procedure', 's_index_message'); create index forums_content_idx on forums_messages (content) indextype is ctxsys.context parameters ('datastore forums_user_datastore'); declare v_job number; begin dbms_job.submit( job => v_job, what => 'ctxsys.ctx_ddl.sync_index(''forums_content_idx'');', interval => 'sysdate + 1/24' ); end; / show errors -- as normal user connect yon/yon; -- ripped off from site-wide-search -- if we pass in a very long string to im_convert, we will end up with internal -- strings that are too long. Because this is relatively hard to debug, -- we wrote im_convert_length_check to throw a more appropriate error message -- Note that we raise an exception because passing such a long query to -- interMedia is pretty slow. Alternative to the application error are to -- 1. return the string as is -- 2. increase the max length from 256 to 1024 -- mbryzek@arsdigita.com, 7/6/2000 create or replace procedure im_convert_length_check ( p_string in varchar2, p_number_chars_to_append in number, p_max_length in number, p_variable_name in varchar2 ) is begin if nvl(length(p_string),0) + p_number_chars_to_append > p_max_length then raise_application_error(-20000, 'Variable "' || p_variable_name || '" exceeds ' || p_max_length || ' character declaration'); end if; end; / show errors; -- this proc takes user supplied free text and transforms it into an interMedia -- friendly query string. (provided by oracle). create or replace function im_convert ( query in varchar2 default null ) return varchar2 is i number := 0; len number := 0; char varchar2(1); minusString varchar2(256) := ''; plusString varchar2(256) := ''; mainString varchar2(256) := ''; mainAboutString varchar2(500) := ''; finalString varchar2(500) := ''; hasMain number := 0; hasPlus number := 0; hasMinus number := 0; token varchar2(256); tokenStart number := 1; tokenFinish number := 0; inPhrase number := 0; inPlus number := 0; inWord number := 0; inMinus number := 0; completePhrase number := 0; completeWord number := 0; code number := 0; begin len := length(query); -- we iterate over the string to find special web operators for i in 1..len loop char := substr(query,i,1); if(char = '"') then if(inPhrase = 0) then inPhrase := 1; tokenStart := i; else inPhrase := 0; completePhrase := 1; tokenFinish := i-1; end if; elsif(char = ' ') then if(inPhrase = 0) then completeWord := 1; tokenFinish := i-1; end if; elsif(char = '+') then inPlus := 1; tokenStart := i+1; elsif((char = '-') and (i = tokenStart)) then inMinus :=1; tokenStart := i+1; end if; if(completeWord=1) then token := '{ '||substr(query,tokenStart,tokenFinish-tokenStart+1)||' }'; if(inPlus=1) then im_convert_length_check(plusString, 4+length(token), 256, 'plusString'); plusString := plusString||','||token||'*10'; hasPlus :=1; elsif(inMinus=1) then im_convert_length_check(minusString, 4+length(token), 256, 'minusString'); minusString := minusString||'OR '||token||' '; hasMinus :=1; else im_convert_length_check(mainString, 6+length(token), 256, 'mainString'); mainString := mainString||' NEAR '||token; im_convert_length_check(mainAboutString, 1+length(token), 500, 'mainAboutString'); mainAboutString := mainAboutString||' '||token; hasMain :=1; end if; tokenStart :=i+1; tokenFinish :=0; inPlus := 0; inMinus :=0; end if; completePhrase := 0; completeWord :=0; end loop; -- find the last token token := '{ '||substr(query,tokenStart,len-tokenStart+1)||' }'; if(inPlus=1) then im_convert_length_check(plusString, 4+length(token), 256, 'plusString'); plusString := plusString||','||token||'*10'; hasPlus :=1; elsif(inMinus=1) then im_convert_length_check(minusString, 4+length(token), 256, 'minusString'); minusString := minusString||'OR '||token||' '; hasMinus :=1; else im_convert_length_check(mainString, 6+length(token), 256, 'mainString'); mainString := mainString||' NEAR '||token; im_convert_length_check(mainAboutString, 1+length(token), 500, 'mainAboutString'); mainAboutString := mainAboutString||' '||token; hasMain :=1; end if; mainString := substr(mainString,6,length(mainString)-5); mainAboutString := replace(mainAboutString,'{',' '); mainAboutString := replace(mainAboutString,'}',' '); mainAboutString := replace(mainAboutString,')',' '); mainAboutString := replace(mainAboutString,'(',' '); plusString := substr(plusString,2,length(plusString)-1); minusString := substr(minusString,4,length(minusString)-4); -- let's just check once for the length of finalString... note this uses the -- longest possible string that is created in the rest of this function im_convert_length_check(finalString, nvl(length(mainString),0) + nvl(length(mainAboutString),0) + nvl(length(minusString),0) + nvl(length(plusString),0) + 30, 500, 'finalString'); -- we find the components present and then process them based on the specific combinations code := hasMain*4+hasPlus*2+hasMinus; if(code = 7) then finalString := '('||plusString||','||mainString||'*2.0,about('||mainAboutString||')*0.5) NOT ('||minusString||')'; elsif (code = 6) then finalString := plusString||','||mainString||'*2.0'||',about('||mainAboutString||')*0.5'; elsif (code = 5) then finalString := '('||mainString||',about('||mainAboutString||')) NOT ('||minusString||')'; elsif (code = 4) then finalString := mainString; finalString := replace(finalString,'*1,',NULL); finalString := '('||finalString||')*2.0,about('||mainAboutString||')'; elsif (code = 3) then finalString := '('||plusString||') NOT ('||minusString||')'; elsif (code = 2) then finalString := plusString; elsif (code = 1) then -- not is a binary operator for intermedia text finalString := 'totallyImpossibleString'||' NOT ('||minusString||')'; elsif (code = 0) then finalString := ''; end if; return finalString; end; / show errors;