Hello Tom,

I came across the structure where in users creating the table or updating the table uses the predicate as
"rownum exec dbms_stats.gather_table_stats(xx,xx)". Can you help us to explain how this predicate structure how it works in Create Table and Update Table statements. Below are the two example mentioned. I am assuming that this will gather table statistics but the doubt is how/why to use in where clause as predicate?

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Example1:-
create table tab as
select object_id as col from all_objects
where rownum exec dbms_stats.gather_table_stats(ownname=>user, tabname=>'TAB');

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Example2:-
update tab set col = 1
where rownum exec dbms_stats.gather_table_stats(ownname=>user, tabname=>'TAB', cascade=>true);

How many rows in the table will update here since use of this predicate? will this update all the records or how much ?
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I've tried searching over the internet to find the explanation with respect to this but no luck. If you can explain or point me to some direction of this how the gathering the table statistics works while used in predicates. Thank you in advance.

SQL> create table tab as
  2  select object_id as col from all_objects
  3  where rownum exec dbms_stats.gather_table_stats(ownname=>user, tabname=>'TAB');
where rownum exec dbms_stats.gather_table_stats(ownname=>user, tabname=>'TAB')
             *
ERROR at line 3:
ORA-00920: invalid relational operator

SQL> create table tab as
  2  select object_id as col from all_objects
  3  where rownum <= 1000;

SQL> exec dbms_stats.gather_table_stats(ownname=>user, tabname=>'TAB');