How to pass table name as argument to cursor

Question

please help me how to solve this.
SQL> select c1 from test ;
C1
1
7
18
4
10
28
30
I'm able to execute this.
SQL> get b
1 set serveroutput on size 2000
2 declare
3 cursor c1 is
4 select c1 from test ;
5 begin
6 for rec in c1
7 loop
8 dbms_output.put_line(rec.c1);
9 end loop;
10* end;
SQL> sta b
1
7
18
4
10
28
30
When I change the above cursor to accept the parameter it is not working.
SQL> get c
1 set serveroutput on size 2000
2 declare
3 cursor c1(p_table varchar2) is
4 select c1 from p_table ;
5 begin
6 for rec in c1('test')
7 loop
8 dbms_output.put_line(rec.c1);
9 end loop;
10* end;
ERROR at line 3:
ORA-06550: line 3, column 18:
PL/SQL: ORA-00942: table or view does not exist
ORA-06550: line 3, column 3:
PL/SQL: SQL Statement ignored
ORA-06550: line 7, column 25:
PLS-00364: loop index variable 'REC' use is invalid
ORA-06550: line 7, column 4:
PL/SQL: Statement ignored

Answer 1

You cannot use a (bind) variable in SQL for an object name (i.e. a table name, column name, etc).
Why?
The SQL engine needs to parse the SQL. Part of the parse is to resolve the scope to determine what objects are being reference. It needs to check that the column names referred to is indeed in that object. Etc.
Then these objects are used to determine the best execution path to run the SQL. What indexes do the objects have? Is the object a partitioned table and the partition criteria used in the predicate? Etc.
How can the SQL engine perform any of these when you pass it a table name that is a parameter?
The name of an object (such as the table being selected from) must be explicitly stated in a SQL statement. It cannot be variable.