How many buckets

Hello Experts,

I need your comments on below topic.

Oracle generating 2 buckets for each column if I am executing this command.

SQL> analyze table t compute statistics;

Table analyzed.

SQL> select count(*),column_name from user_Tab_histograms where table_name = 'T' group by column_name;

  COUNT(*) COLUMN_NAME
---------- --------------------------------------------------

         2 CREATED
         2 DATA_OBJECT_ID
         2 GENERATED
         2 LAST_DDL_TIME
         2 OBJECT_ID
         2 OBJECT_NAME
         2 OBJECT_TYPE
         2 OWNER
         2 SECONDARY
         2 STATUS
         2 SUBOBJECT_NAME
         2 TEMPORARY
         2 TIMESTAMP

13 rows selected.

And If use this command ...

SQL> analyze table t compute statistics for table for all columns;

Table analyzed.

SQL> select count(*),column_name from user_Tab_histograms where table_name = 'T' group by column_name;

  COUNT(*) COLUMN_NAME
---------- --------------------------------------------------

        76 CREATED
        75 DATA_OBJECT_ID
         2 GENERATED
        76 LAST_DDL_TIME
        76 OBJECT_ID
        76 OBJECT_NAME
        24 OBJECT_TYPE
        11 OWNER
         1 SECONDARY
         2 STATUS
         2 SUBOBJECT_NAME
         2 TEMPORARY
        76 TIMESTAMP

I am confused .. No of buckets is dependent upon what ?

Regards. Received on Tue Dec 20 2005 - 12:41:28 CST