SQL statements for common table operations in Oracle

Drop table test2; create table test (id integer not null, name varchar2 (100); --- empty alter table test modify (id null ); --- empty alter table test modify (id not null); --- add the alter table + add Clause alter table test add (ceilphone varchar2 (20) in the table )); --- modify the alter table + modify clause in the table. If it is not empty, update the statement first, and then modify alter table test modify (ceilphone integer ); ---- Delete the alter table test drop column ceilphone; --- rename the alter table test rename to test2;



Excerpted from the column of wandering hacker