Regular expression vs oracle text performance

Question

Does anyone have experience with comparig performance of regular expression vs oracle text?
We need to implement a text search on a large volume table, 100K-500K rows.
The select stmt will select from a VL, a view joining 2 tables, B and _TL.
We need to search 2 text columns from this _VL view.
Using regex seems less complex, but the deciding factor is of course performace.
Would oracle text search perform better than regular expression in general?
Thanks,
Margaret

Answer 1

Hi Dominc,
Thanks, we'll try both...
Would you be able to validate our code to create the multi-table index:
CREATE OR REPLACE PACKAGE requirements_util AS
PROCEDURE concat_columns(i_rowid IN ROWID, io_text IN OUT NOCOPY VARCHAR2);
END requirements_util;
CREATE OR REPLACE PACKAGE BODY requirements_util AS
PROCEDURE concat_columns(i_rowid IN ROWID, io_text IN OUT NOCOPY VARCHAR2)
AS
tl_req pjt_requirements_tl%ROWTYPE;
b_req pjt_requirements_b%ROWTYPE;
CURSOR cur_req_name (i_rqmt_id IN pjt_requirements_tl.rqmt_id%TYPE) IS
SELECT rqmt_name FROM pjt_requirements_tl
WHERE rqmt_id = i_rqmt_id;
PROCEDURE add_piece(i_add_str IN VARCHAR2) IS
lx_too_big EXCEPTION;
PRAGMA EXCEPTION_INIT(lx_too_big, -6502);
BEGIN
io_text := io_text||' '||i_add_str;
EXCEPTION WHEN lx_too_big THEN NULL; -- silently don't add the string.
END add_piece;
BEGIN
     BEGIN
          SELECT * INTO b_req FROM pjt_requirements_b WHERE ROWID = i_rowid;
          EXCEPTION
          WHEN NO DATA_FOUND THEN
          RETURN;
     END;
     add_piece(b_req.req_code);
     FOR tl_req IN cur_req_name(b_req.rqmt_id) LOOP
     add_piece(tl_req.rqmt_name);
END concat_columns;
END requirements_util;
EXEC ctx_ddl.drop_section_group('rqmt_sectioner');
EXEC ctx_ddl.drop_preference('rqmt_user_ds');
BEGIN
ctx_ddl.create_preference('rqmt_user_ds', 'USER_DATASTORE');
ctx_ddl.set_attribute('rqmt_user_ds', 'procedure', sys_context('userenv','current_schema')||'.'||'requirements_util.concat_columns');
ctx_ddl.set_attribute('rqmt_user_ds', 'output_type', 'VARCHAR2');
END;
CREATE INDEX rqmt_cidx ON pjt_requirements_b(req_code)
INDEXTYPE IS CTXSYS.CONTEXT
PARAMETERS ('DATASTORE rqmt_user_ds
SYNC (ON COMMIT)');