Count of Table's Rows per Datafile

set verify off
def tabowner = &&1
def tabname = &&2

ttitle -
center '&tabowner..&tabname Rows per Datafile' skip 3

col file# format 99,999 justify c heading 'Datafile ID'
col nrows format 999,999,999,999 justify c heading 'Row Count'

select dbms_rowid.rowid_to_absolute_fno(rowid,'&&tabowner','&&tabname') file#,
count(rowid) nrows
from &&tabowner..&&tabname
group by dbms_rowid.rowid_to_absolute_fno(rowid,'&&tabowner','&&tabname')
/

undef tabowner
undef tabname
set verify on