Which user does the Oracle query table belong?

Select username, default_tablespace from dba_users order by username

You must have dba permissions.

1. view the user's default tablespace name

You must know your login user name, right,

Log On With sysdba.

Sqlplus/as sysdba

Select username, default_tablespace from dba_users;

2. view the total table space size and the used table space size.

Select a. tablespace_name, a. bytes/1024/1024 "Sum MB", (a. bytes-b.bytes)/1024/1024 "used MB", B. bytes/1024/1024 "free MB ",

Round (a. bytes-b.bytes)/a. bytes) *) "percent_used"

From

(Select tablespace_name, sum (bytes) bytes from dba_data_files group by tablespace_name),

(Select tablespace_name, sum (bytes) bytes, max (bytes) largest from dba_free_space group by tablespace_name) B

Where a. tablespace_name = B. tablespace_name

Order by (a. bytes-b.bytes)/a. bytes) desc;