Which MySQL DDL Statements Can Be Directly Executed in GaussDB(DWS)?

During the real-time synchronization from MySQL to GaussDB(DWS), DRS does not convert incremental MySQL DDL statements, but directly executes these DDL statements in GaussDB(DWS). The following DDL statements can be directly executed in GaussDB(DWS):

alter table test add column c1 varchar(20);  
alter table test  drop column c1;  
drop table test;  
create table test(id int primary key ,name varchar(20)); 
create index test on db1.test (name); 
truncate table db1.test;

The following DDL statements cannot be directly executed:

alter table db1.test rename to db1.test_bak;
rename table test to test_bak;
alter table db1.test modify column c1 varchar(40);
alter table db1.test change column c1 c1 varchar(50);
alter table db1.test add index/key index_1(name);
alter table db1.test drop index/key index_1;