DRG-11112: length of CLOB query value exceeds maximum of 64000

Question

Is there a CLOB length limitation when running an Oracle Text search? (v 11.1.0.7) I have checked the Reference Guide and Application Developer's Guide.
--create table
create table nk_1929(id number, vc_a clob);
--insert dummy data
declare
vc_clob clob;
begin
vc_clob := lpad(to_clob('a'), 222920, 'a');
insert into nk_1929 values(1, vc_clob);
end;
--create index
create index nk_1929_ndx on nk_1929(vc_a)
indextype is ctxsys.context parameters('
datastore ctxsys.default_datastore
stoplist ctxsys.empty_stoplist');
--run query with a search string longer than 64000
declare
str1 clob;
query_term clob;
begin
select vc_a into query_term from nk_1929 where id = 1;
str1 := 'select id from nk_1929 where contains(vc_a, :1) > 0';
execute immediate str1 using query_term;
end;
ORA-29902: error in executing ODCIIndexStart() routine
ORA-20000: Oracle Text error:
DRG-11112: length of CLOB Query Value exceeds maximum of 64000
Please let me know if I am missing something here?

Answer 1

Same 64000 CLOB query value limitation is also generated with a simple select:
--run query with a search string longer than 64000
declare
vn_id number;
query_term clob;
begin
select vc_a into query_term from nk_1929 where id = 1;
select max(id) into vn_id from nk_1929 where contains(vc_a, query_term) > 0;
end;
ORA-29902: error in executing ODCIIndexStart() routine
ORA-20000: Oracle Text error:
DRG-11112: length of CLOB Query Value exceeds maximum of 64000