1、表名，小写转大写。如下：my_test转换MY_TEST

DECLARE
    v_tablename_x VARCHAR2(20);
    v_tablename_d VARCHAR2(20);
begin
    v_tablename_x:='my_test';
    v_tablename_d:='MY_TEST';
    execute immediate 'alter table "'||v_tablename_x||'" rename to '||v_tablename_d||'';
exception
    when others then
    dbms_output.put_line(v_tablename_d||'已存在');
end;

2、列名，小写转大写

DECLARE
    v_tablename_d VARCHAR2(20);

begin
    v_tablename_d:='MY_TEST';
    for c in (select COLUMN_NAME cn from all_tab_columns where table_name=v_tablename_d) loop
    begin
        execute immediate 'alter table "'||v_tablename_d||'" rename column "'||c.cn||'" to '||c.cn;
        exception
        when others then
        dbms_output.put_line(v_tablename_d||'.'||c.cn||'已经存在');
    end;
    end loop;
end;

3、表和列一起，小写转大写

DECLARE
    v_tablename_x VARCHAR2(20);
    v_tablename_d VARCHAR2(20);

begin
    v_tablename_x:='my_test';
    v_tablename_d:='MY_TEST';
    for c in (select COLUMN_NAME cn from all_tab_columns where table_name=v_tablename_x) loop
    begin
        execute immediate 'alter table "'||v_tablename_x||'" rename column "'||c.cn||'" to '||c.cn;
        exception
        when others then
        dbms_output.put_line(v_tablename_x||'.'||c.cn||'已经存在');
    end;
    end loop;

    execute immediate 'alter table "'||v_tablename_x||'" rename to '||v_tablename_d||'';
    exception
    when others then
    dbms_output.put_line(v_tablename_d||'已存在');
end;

4、表和列一起，大写转小写

DECLARE
    v_tablename_x VARCHAR2(20);
    v_tablename_d VARCHAR2(20);

begin
    v_tablename_x:='my_test';
    v_tablename_d:='MY_TEST';

    for c in (select COLUMN_NAME cn from all_tab_columns where table_name=v_tablename_d) loop
        begin
            execute immediate 'alter table '||v_tablename_d||' rename column '||c.cn||' to "'||LOWER(c.cn)||'"';
            exception
            when others then
            dbms_output.put_line(v_tablename_d||'.'||c.cn||'已经存在');
        end;
    end loop;

    execute immediate 'alter table '||v_tablename_d||' rename to "'||v_tablename_x||'"';
    exception
    when others then
    dbms_output.put_line(v_tablename_x||'已存在');
end;

5、列名，大写转小写

DECLARE
    v_tablename_d VARCHAR2(20);

begin
    v_tablename_d:='MY_TEST';

    for c in (select COLUMN_NAME cn from all_tab_columns where table_name=v_tablename_d) loop
        begin
            execute immediate 'alter table '||v_tablename_d||' rename column '||c.cn||' to "'||LOWER(c.cn)||'"';
            exception
            when others then
            dbms_output.put_line(v_tablename_d||'.'||c.cn||'已经存在');
        end;
    end loop;
end;

6、表名，大写转小写

DECLARE
    v_tablename_x VARCHAR2(20);
    v_tablename_d VARCHAR2(20);

begin
    v_tablename_x:='my_test';
    v_tablename_d:='MY_TEST';

    execute immediate 'alter table '||v_tablename_d||' rename to "'||v_tablename_x||'"';
    exception
    when others then
    dbms_output.put_line(v_tablename_x||'已存在');
end;