Which partition?

Question

Is there anyway to find out which particular partition has been made use of,from the explain plan of a query?
I see something like the ones below in the explain plan..
| Id  | Operation                              |  Name                  | Rows  | Bytes | Cost  | Pstart| Pstop |
|12 |    PARTITION RANGE ALL                 |                        |       |       |       |     1 |   506 |but nothing informative of the Partition name.
Thoughts plz..
Regards,
Bhagat

Answer 1

If the query can be constrained to certain partitions only, then only those partitions will be used.
E.g. table is defined a ranged partition with a partition per INVOICE_DATE. The SQL is:
SELECT ..some stuff.. FROM invoice WHERE invoice_date BETWEEN :0 and :1
The CBO can determine which partitions contains rows for that invoice data range.
When the query cannot be constrained to certain partitions only, then all partitions need to be included.
E.g
SELECT ..some stuff.. FROM invoices WHERE cust_id = :0
PS. The Pstart and PStop of the execution plan will indicate the above. A range of partitions, all partitions, or specific partitions. A partition range can also be given in the execution plan as a bind variable - i.e. the CBO will at runtime look at the bind values supplied and then determine the actual partitions to scan.