Row Count from all tables

This script will count the rows of all tables from a schema (prod).

 conn prod/pass

CREATE TABLE TABLECNT (TABLE_NAME VARCHAR2(40 CHAR), NUM_ROWS INTEGER);

declare row_cnt number;
begin 
for x in (select table_name from user_tables order by table_name) 
loop 
 execute immediate 'select count(*) from ' ||x.table_name into row_cnt; 
 insert into tablecnt values(x.table_name,row_cnt); 
 end loop;
end;
/

select * from TABLECNT order by NUM_ROWS desc;