Evaluating an expression in a string

Question

I need to evaluate an expression in a string, and return 0 or 1 for true or false.
Here is a version I tried:
06:25:26  > CREATE OR REPLACE FUNCTION MJT_EVALUATE_EXPR (in_expr_to_evaluate VARCHAR2)
06:26:00   2     RETURN NUMBER
06:26:00   3  IS
06:26:00   4     l_dual_record   DUAL%ROWTYPE;
06:26:00   5     csr_dual        SYS_REFCURSOR;
06:26:00   6     l_this_result   NUMBER;
06:26:00   7  BEGIN
06:26:00   8     OPEN csr_dual FOR 'SELECT * FROM DUAL WHERE ' || in_expr_to_evaluate;
06:26:00   9 
06:26:00  10     FETCH csr_dual INTO l_dual_record;
06:26:00  11 
06:26:00  12     IF csr_dual%FOUND
06:26:00  13     THEN
06:26:00  14        l_this_result := 1;
06:26:00  15     ELSE
06:26:00  16        l_this_result := 0;
06:26:00  17     END IF;
06:26:00  18 
06:26:00  19     CLOSE csr_dual;
06:26:00  20 
06:26:00  21     RETURN l_this_result;
06:26:00  22  END;
06:26:00  23  /
Function created.
06:26:11> select mjt_evaluate_expr('((1=1) OR (1=0))') from dual;
MJT_EVALUATE_EXPR('((1=1)OR(1=0))')
                                  1
1 row selected.
Elapsed: 00:00:00.02
06:26:22 > Due to the high number of executions, I would like to avoid dynamic SQL or cursor operations such as this. Does anyone have a suggestion for another approach?
The expressions can get more complex than this, possibly with dozens of terms.

Answer 1

Does anyone have a suggestion for another approach?I don't think you'll gain any performance but for the records:
SQL> select * from v$version where rownum = 1
BANNER                                                                         
Oracle Database 11g Enterprise Edition Release 11.2.0.2.0 - Production         
1 row selected.
SQL> var bool varchar2(40)
SQL> exec :bool := '1=1 and 1=0'
PL/SQL procedure successfully completed.
SQL> select decode(column_value, 'true', 1, 0) bool from xmltable (:bool)
      BOOL
         0
1 row selected.