Your question "Fetch out of sequence error" does not have anything to do with your clarification.
You can assign one Ref Cursor to another, but why do you have to do that?
Consider the below example,
OPEN l_rc_var1 FOR SELECT * FROM dual;
FETCH l_rc_var2 INTO l_vc_var3;
Error report -
ORA-01001: invalid cursor
ORA-06512: at line 11
01001. 00000 - "invalid cursor"
Here, I have assigned the sys_refcursor L_RC_VAR1 to L_RC_VAR2 variable. Now, both has the same cursor ID internally.
You can open L_RC_VAR2 and internally L_RC_VAR1 also gets opened.
If you close L_RC_VAR2, internally L_RC_VAR1 also gets closed. So, its just a mirror copy, which I dont feel of any use.
Please post your requirement for adding a new sys ref cursor OUT parameter, so that we can see what is the best way to do it.
Also, if you are unsure about the number of Ref cursor OUT parameters, you can very well use the implicit result sets technique (12c and later only). Excerpts given below,http://www.dba-oracle.com/t_adv_plsql_impl...result_sets.htmhttp://www.dba-oracle.com/t_adv_plsql_get_next_result.htm