Which two statements are true?

You are measuring the I/O savings provided by storage indexes for Table A. One of your scripts
displays the I/O savings as a result of the storage indexes. Which two statements are true?
SQL> select count (*) from transmap.mymap_comp
2 where map_id between 400 and 500;
COUNT(*)
—————————————103000
Elapsed: 00:00:00.08
SQL> select b.name, a.value/1024/1024 value
from vSmystat a, vSstatname b,
where b.statistic# = a.statistic#

and b.nafne in (•cell physical IO bytes eligible for predicate offload’,
•cell physical IO interconnect bytes’,
•cell physical IO bytes saved by storage index’,
•cell physical IO interconnect bytes returned by smart scan’) order by 1;
Statistic Value (MB)
——————————————————————————————— —————–cell physical IO bytes eligible for predicate offload 2,255 .09
cell physical IO bytes saved by storage index .00
cell physical IO interconnect bytes 1.72
cell physical IO interconnect bytes returned by smart scan 1.68

You are measuring the I/O savings provided by storage indexes for Table A. One of your scripts
displays the I/O savings as a result of the storage indexes. Which two statements are true?
SQL> select count (*) from transmap.mymap_comp
2 where map_id between 400 and 500;
COUNT(*)
—————————————103000
Elapsed: 00:00:00.08
SQL> select b.name, a.value/1024/1024 value
from vSmystat a, vSstatname b,
where b.statistic# = a.statistic#

and b.nafne in (•cell physical IO bytes eligible for predicate offload’,
•cell physical IO interconnect bytes’,
•cell physical IO bytes saved by storage index’,
•cell physical IO interconnect bytes returned by smart scan’) order by 1;
Statistic Value (MB)
——————————————————————————————— —————–cell physical IO bytes eligible for predicate offload 2,255 .09
cell physical IO bytes saved by storage index .00
cell physical IO interconnect bytes 1.72
cell physical IO interconnect bytes returned by smart scan 1.68

A.
The storage indexes were disabled using the disable_storage_INDEX Parameter.

B.
Storage Index data is not on the Cell Server’s region index memory structures yet because this
predicate has not been used.

C.
Since the database was started, no quires were run against this table with the same predicate.

D.
The storage indexes reduced the amount of physical I/O bytes significantly for this query.

Explanation:
* cell physical I/O bytes eligible for predicate offload
Number of bytes eligible for predicate offload, an indication of smart scan
* (not D) cell physical I/O bytes saved by storage index
Here 0.
Number of bytes saved by a storage index; this is a reflection of how
many physical disk I/O bytes (and by proxy, requests) were saved
due to a storage index eliminating candidate blocks



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Syed Jaffer Hussain

Syed Jaffer Hussain

BC