Cost of delete

Question

Would the cost (time) to use
delete from table where rowid in ( select rowid from table1,table2, table2 where ...)
be same or nearly same as using select query if the select query does not fetch any records?

Answer 1

I am deleting some records using complex sql but in most cases it does not delete any records. I wanted to know if the cost or the time it takes for this delete statement to execute will be same as executing just the select statement if no rows are returned?
I am using oracle 10g. I am assuming that since no rows are returned so oracle does not have to actually delete anything so there will not be any overhead of creating redo logs.. etc.
Hence , using delete with select in the where condition would be same as just using select statement. Is my assumption correct?
Following is my delete statement.
DELETE FROM table_name
WHERE ROWID IN (
SELECT c.ROWID
FROM table_name c, clm_run_error cre, clm_hdr_clm_ln_run_detail chcld
WHERE c.clm_run_error_sid = cre.clm_run_error_sid
AND cre.clm_hdr_clm_ln_run_detail_sid = chcld.clm_hdr_clm_ln_run_detail_sid
AND chcld.claim_header_sid = crec1.claim_header_sid
AND NVL (chcld.claim_line_sid, 0) = NVL (crec1.claim_line_sid, 0)
AND cre.clm_error_sid = v_clm_error_sid);
Thanks a lot for your asssistance.