没有区别，如果你的scott用户有默认表空间，这个表就会建在默认表空间里，如果没有默认表空间，就会建在users的表空间里。

SQL> create user test identified by test default tablespace test;

User created.

SQL> create user test1 identified by test1;

User created.

SQL> select username,default_tablespace from dba_users where username like '%TEST%';

USERNAME DEFAULT_TABLESPACE
------------------------------ ------------------------------
TEST TEST
TEST1 USERS

SQL> create table test.haha(id int);

Table created.

SQL> create table test1.haha(id int);

Table created.

SQL> conn test/test
Connected.
SQL> create table test_haha(id int);

SQL> select owner,tablespace_name,table_name from dba_tables where table_name like '%HAHA%';

OWNER TABLESPACE_NAME
------------------------------ ------------------------------
TABLE_NAME
------------------------------
TEST TEST
HAHA

TEST1 USERS
HAHA

TEST TEST
TEST_HAHA