clob类型转换为string类型的orcal函数

create or replace function clob_to_string(

table_name in varchar2,

field_id in varchar2,

field_name in varchar2,

v_id in number,

v_pos in number) return varchar2

is

lobloc clob;

buffer varchar2(32767);

amount number := 2000;

offset number := 1;

query_str varchar2(1000);

begin

query_str := 'select '||field_name|| ' from '||table_name|| ' where '||field_id|| '= :id ';

EXECUTE IMMEDIATE query_str INTO lobloc USING v_id;

offset:=offset+(v_pos-1)*2000;

dbms_lob.read(lobloc,amount,offset,buffer);

return buffer;

exception

when no_data_found then

return buffer;

end;

CREATE OR REPLACE FUNCTION CLOB_TO_STRING (clob_in IN CLOB) RETURN CLOB

AS

offset INTEGER;

amount INTEGER;

output VARCHAR2(32767);

BEGIN

offset := 1;

amount := 32767;

LOOP

DBMS_LOB.read(clob_in,amount,offset,output);

--DBMS_OUPUT.PUT_LINE(output);

offset := offset + amount;

END LOOP;

return output;

EXCEPTION

WHEN NO_DATA_FOUND THEN

return output;

END CLOB_TO_STRING;

SELECT

c.catentry_id,xcs.store_id,xcs.field2 as author,

(select xcac.content from X_CATENTRY_ATTR_CLOB xcac where c.catentry_id = xcac.catentry_id(+) and xcs.store_id = xcac.store_id(+))

as fieldsAll,

sc.catalog_id,c.partnumber,g.member_id,null as parentCatentry_id,c.catenttype_id,