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thanks for reply. N its abt discussion n not arguments.
Well i m new to partitioned objects world.if sb else can put this notion into my mind, i shall be obliged.
commands i executed are:
SQL> create table sales (
2 amount number(5),
3 week_no number(2))
4 partition by range (week_no)
5 (partition p1 values less than (2) tablespace users,
6 partition p2 values less than (6) tablespace example,
7 partition p3 values less than (maxvalue) tablespace xdb);
Table created.
SQL> ed
Wrote file afiedt.buf
1 create index test on sales(amount)
2 global
3 partition by range(amount)
4 (partition p11 values less than (4000) tablespace users,
5 partition p22 values less than (14000) tablespace example,
6* partition p33 values less than (maxvalue) tablespace xdb)
SQL> /
Index created.
SQL> @E:\oracle\ora92\rdbms\admin\utlxplan
Table created.
SQL> explain plan for select * from sales where amount=13000;
Explained.
SQL> select operation,options from plan_table;
OPERATION OPTIONS
------------------------------ -----------------------------------------
SELECT STATEMENT
TABLE ACCESS BY GLOBAL INDEX ROWID
INDEX RANGE SCAN
didnt get it--not supported by oracle.
Secondly, it wud be beneficial for queries that use where condition on sales_amount column. Though partitions were made in lieu of queries using week_no; but if v have queries that also use sales_amoun, then the index wud be beneficial. I feel this is a better option, as entries in one partition of index will point to rowids in different table partitions, than going for non-prefixed local partitioned index,where we will have m:n index-table partition mapping. The benefits seem to be clear to me this way.
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