PL/SQL User’s Guide and Reference - Phần 7

Dynamic SQL supports all the SQL datatypes. So, for example, define variables and bind arguments can be collections, LOBs, instances of an object type, and refs. As a rule, dynamic SQL does not support PL/SQL-specific types. So, for example, define variables and bind arguments cannot be Booleans or index-by tables. The only exception is that a PL/SQL record can appear in the INTO clause. You can execute a dynamic SQL statement repeatedly using new values for the bind arguments. However, you incur some overhead because EXECUTE IMMEDIATE re-prepares the dynamic string before every execution.