Which statements are true about the tuning of PL/SQL code? (Choose two.) 

Answer options:

A. Redundant SQL statements in PL/SQL code should be avoided
B. Implicit data type conversion in PL/SQL code can improve performance
C. Usage of the NOT NULL constraint in PL/SQL code can degrade performance
D. If you have one PL/SQL program unit instead of multiple smaller executable sections, performance can be improved

AC