How to pass dynamically constructed string to where clause

Question

select name from mytable
where l_condition
and sal=20;
l_condition is value coming from the function.
ex: l_condition is first_name='abc' and last_name='xyz' and first_name='def' and last_name='zef'

Answer 1

Dynamic SQL can help in this case:
variable ref refcursor
DECLARE
  l_condition VARCHAR2(1000) :=
      ' salary > 3000  and first_name like ''L%''';
BEGIN
  OPEN :REF FOR
  ' SELECT first_name, salary FROM hr.employees ' ||
  ' WHERE ' || l_condition;
END;
print :ref;
FIRST_NAME           SALARY                
Laura                3630                  
Lindsey              8800                  
Lex                  18700                 
Luis                 7590                  
Louise               8250                  
Lisa                 12650