Number of tables in schema

Question

Hi all,
i was used following queries to find no of tables in a schema
select * from tab;
and
select count(table_name) from user_tables;
These 2 queries returning 2 different answers
Can you please tell me what is the difference between these 2 queries?
What is exact query to find total no of tables in a schema?
Thanks

Answer 1

These are both views with different object source and condition. Better use user_tables
USER_TABLES:
select columns...
from sys.ts$ ts, sys.seg$ s, sys.obj$ co, sys.tab$ t, sys.obj$ o,
     sys.obj$ cx, sys.user$ cu, x$ksppcv ksppcv, x$ksppi ksppi
where o.owner# = userenv('SCHEMAID')
  and o.obj# = t.obj#
  and bitand(t.property, 1) = 0
  and bitand(o.flags, 128) = 0
  and t.bobj# = co.obj# (+)
  and t.ts# = ts.ts#
  and t.file# = s.file# (+)
  and t.block# = s.block# (+)
  and t.ts# = s.ts# (+)
  and t.dataobj# = cx.obj# (+)
  and cx.owner# = cu.user# (+)
  and ksppi.indx = ksppcv.indx
  and ksppi.ksppinm = '_dml_monitoring_enabled'
TAB:
select columns...
  from  sys.tab$ t, sys.obj$ o
  where o.owner# = userenv('SCHEMAID')
  and o.type# >=2
  and o.type# <=5
  and o.linkname is null
  and o.obj# = t.obj# (+)