Please help to understand 10g explain plan

Hello
I am trying to optimize one query. I have taken explain plan of this query in 9i and 10g database both.
Explain plan for index scan is different in 9i and 10g. In 9i inedex was scaned with INDEX RANGE SCAN NON-UNIQUE and in 10g index is scanned with
INDEX RANGE SCAN.
Can anybody explain the difference of scanning an index in 9i and 10g? Cost in 9i was 74 and now in 10g it is 1134.
Thanks in advance

Well, if you tables structures and indexes are the same in both databases then that's unlikely to be an issue, however you need to check other factors such as whether statistics have been gathered for the data recently.
For helpful info on optimising queries and what to look out for read the following thread...
[When your query takes too long|http://forums.oracle.com/forums/thread.jspa?messageID=1812597#1812597]

Similar Messages

Help to understand the explain plan

Hi, Everyone,
i have query :
INSERT INTO ICM_UPSEL_1_ALL
select a.customer_no,a.pr_code_bbl,min(b.pr_code_pmm) pr_code_pmm,a.score,a.price_diff,a.flag
from ICM_UPSEL_MIN_PRDIFF_1 a, icm_pre b
where a.customer_no = b.customer_no
and a.pr_code_bbl=b.pr_code_bbl
and a.score = b.score
and a.flag = b.flag
and a.price_diff = b.price_diff
and b.price_diff > 0
and b.score >=0.5
and b.flag = 1
and b.price_diff > 0 and b.price_diff <= 10
group by a.customer_no,a.pr_code_bbl,a.score,a.price_diff,a.flag
This query is running in a pl/sql procedure. The explain plan for this query is :
Plan hash value: 3124235498
| Id | Operation                       | Name                           | Rows | Bytes | Cost (%CPU)| Time     |
|   0 | INSERT STATEMENT                |                                |     1 |   143 |     4 (25)| 00:00:01 |
|   1 | LOAD TABLE CONVENTIONAL        | ICM_UPSEL_1_ALL        |       |       |            |          |
|   2 |   HASH GROUP BY                 |                                |     1 |   143 |     4 (25)| 00:00:01 |
|   3 |    NESTED LOOPS                 |                                |       |       |            |          |
|   4 |     NESTED LOOPS                |                                |     1 |   143 |     3   (0)| 00:00:01 |
|* 5 |      TABLE ACCESS BY INDEX ROWID| ICM_UPSEL_MIN_PRDIFF_1 |     1 |    65 |     1   (0)| 00:00:01 |
|* 6 |       INDEX RANGE SCAN          | MPD_1_FLAG_IDX                 |     1 |       |     1   (0)| 00:00:01 |
|* 7 |      INDEX RANGE SCAN           | ICM_PRE_FLAG_IDX               |     1 |       |     2   (0)| 00:00:01 |
|* 8 |     TABLE ACCESS BY INDEX ROWID | ICM_PRE                |     1 |    78 |     2   (0)| 00:00:01 |
Predicate Information (identified by operation id):
   5 - filter("A"."PRICE_DIFF">0 AND "A"."SCORE">=0.5 AND "A"."PRICE_DIFF"<=10)
   6 - access("A"."FLAG"=1)
   7 - access("B"."FLAG"=1)
   8 - filter("B"."PRICE_DIFF"<=10 AND "B"."SCORE">=0.5 AND "B"."PRICE_DIFF">0 AND
              "A"."CUSTOMER_NO"="B"."CUSTOMER_NO" AND "A"."PR_CODE_BBL"="B"."PR_CODE_BBL" AND "A"."SCORE"="B"."SCORE"
              AND "A"."PRICE_DIFF"="B"."PRICE_DIFF")
This query is running for 10 hours now and no result yet. Could anyone please help me where is going wrong... why is it taking so much time to insert the data...
The number of rows in ICM_UPSEL_MIN_PRDIFF_1 : 84,858
The number of rows in icm_pre : 455,500,944
All the columns are indexed.
My database version is 11.1.0.6 running on windows server 2003 R2.
Thanks in advance

Hi, Nikolay,
Please see the results below;
SELECT * FROM DBA_TAB_COL_STATISTICS
WHERE OWNER = 'SAST' AND TABLE_NAME = 'ICM_UPSEL_MIN_PRDIFF_1' AND COLUMN_NAME = 'FLAG';
TABLE_NAME
COLUMN_NAME
NUM_DISTINCT
LOW_VALUE
HIGH_VALUE
DENSITY
NUM_NULLS
NUM_BUCKETS
LAST_ANALYZED
SAMPLE_SIZE
GLOBAL_STATS
USER_STATS
AVG_COL_LEN
HISTOGRAM
SAST    ICM_UPSEL_MIN_PRDIFF_1    FLAG    1    C102    C102    0.00000584543291182618    0    1    16/07/13 10:01:42    5544    YES    NO    3    FREQUENCY
SELECT * FROM DBA_TAB_STATISTICS WHERE OWNER = 'SAST' AND TABLE_NAME = 'ICM_UPSEL_MIN_PRDIFF_1';
TABLE_NAME
PARTITION_NAME
PARTITION_POSITION
SUBPARTITION_NAME
SUBPARTITION_POSITION
OBJECT_TYPE
NUM_ROWS
BLOCKS
EMPTY_BLOCKS
AVG_SPACE
CHAIN_CNT
AVG_ROW_LEN
AVG_SPACE_FREELIST_BLOCKS
NUM_FREELIST_BLOCKS
AVG_CACHED_BLOCKS
AVG_CACHE_HIT_RATIO
SAMPLE_SIZE
LAST_ANALYZED
GLOBAL_STATS
USER_STATS
STATTYPE_LOCKED
STALE_STATS
SAST    ICM_UPSEL_MIN_PRDIFF_1
TABLE    84858    874    0    0    0    62    0    0
84858    16/07/13 10:02:00    YES    NO
NO
Thanks & Regards
Su

Please help to understand the Service parts planning,we r tring to do poc for project

Hi
Please help to understand the Service parts planning,we r tring to do poc for project
1)How the sales history flow from cube to Interactive forecasting screen(like dp in apo there is no Planning area to store data and no load planning area from cube,so please let me know how it will load data?)
2)How the Final demand will flow to DRP for further planning?
3)What is the exact purpose of BOD?
4)What is the leading indicator forecasting and the purpose?
5)Where data will store in SPP (forecasting and other data like liveache in dp)?
6)Product interchangeability and use?
6)Can you please forward the process document to understand the flow as i am not able understand the help document
Thanks for advance help
Regards
kkk

Hi,
Please check Service Part Supply Plan - Enterprise Services in SAP Advanced Planning and Optimization - SAP Library
BR

Please help to understand the Service parts planning doubts/clarifications

Please help to understand the Service parts planning,we r tring to do poc for project
1)How the sales history flow from cube to Interactive forecasting screen(in spp,like dp in apo there is no Planning area to store data and no load planning area from cube,so please let me know how it will sales history load data?)
2)Does Sales History of the child location will agregated to entry level ? if so like that we need to run statistical forecats at entry location?
3)where we will create the from and To Product(eg:Maping Product A to Product B ) to do the Relignment /Phase in profile/Interchangebility
4)What is the leading indicator forecasting and the purpose?
5)Where data will store in SPP (forecasting and other data like liveache in dp)? Mpos and Planning area is not there in SPP?
6)Can you please forward the process document to understand the flow as i am not able understand completely by the help document
Thanks for advance help
Regards
KKK

Hi,
Please check Service Parts Planning - Enterprise Services in SAP Advanced Planning and Optimization - SAP Library
BR

CrashReporter - Could you please help to understand this crash report?

Could you please help to understand this crash report below?
If I'm not wrong it started after update the Mac OS X to version 10.5.6 - every startup.
Note: First update by regular update then after by combo.
Thanks in advance!
_ CrashReporter
Process: aslmanager [218]
Path: /usr/sbin/aslmanager
Identifier: aslmanager
Version: ??? (???)
Code Type: X86 (Native)
Parent Process: launchd [1]
Date/Time: 2009-04-05 08:29:52.069 -0300
OS Version: Mac OS X 10.5.6 (9G55)
Report Version: 6
Exception Type: EXCBADACCESS (SIGSEGV)
Exception Codes: KERNINVALIDADDRESS at 0x0000000000200000
Crashed Thread: 0
Thread 0 Crashed:
0 libSystem.B.dylib 0x952a8a85 asl_get64 + 11
1 libSystem.B.dylib 0x952aa034 aslfile_fetchpos + 939
2 libSystem.B.dylib 0x952aa2f6 aslfilematch + 339
3 aslmanager 0x00002409 0x1000 + 5129
4 aslmanager 0x00002b3e 0x1000 + 6974
5 aslmanager 0x0000211a 0x1000 + 4378
Thread 0 crashed with X86 Thread State (32-bit):
eax: 0x001ffffc ebx: 0x952a9ca1 ecx: 0x00000000 edx: 0x00000000
edi: 0x0000ff3d esi: 0x00100b30 ebp: 0xbffffbc8 esp: 0xbffffba0
ss: 0x0000001f efl: 0x00010286 eip: 0x952a8a85 cs: 0x00000017
ds: 0x0000001f es: 0x0000001f fs: 0x00000000 gs: 0x00000037
cr2: 0x00200000
Binary Images:
0x1000 - 0x2ffd +aslmanager ??? (???) <201b2dea48b8d80ac1432ff85244ed31> /usr/sbin/aslmanager
0x8fe00000 - 0x8fe2db43 dyld 97.1 (???) <100d362e03410f181a34e04e94189ae5> /usr/lib/dyld
0x9444a000 - 0x9444efff libmathCommon.A.dylib ??? (???) /usr/lib/system/libmathCommon.A.dylib
0x951a4000 - 0x951abfe9 libgcc_s.1.dylib ??? (???) <f53c808e87d1184c0f9df63aef53ce0b> /usr/lib/libgcc_s.1.dylib
0x951ba000 - 0x95321ff3 libSystem.B.dylib ??? (???) <d68880dfb1f8becdbdac6928db1510fb> /usr/lib/libSystem.B.dylib
0xffff0000 - 0xffff1780 libSystem.B.dylib ??? (???) /usr/lib/libSystem.B.dylib
_ Log
05/04/09 8:25:58 com.apple.loginwindow[35] Shutdown NOW!
05/04/09 8:25:58 com.apple.loginwindow[35] System shutdown time has arrived
05/04/09 8:25:58 com.apple.SystemStarter[30] Stopping Missing Sync Listener
05/04/09 8:25:58 com.apple.SystemStarter[30] Stopping HP Trap Monitor
05/04/09 8:25:58 com.apple.SystemStarter[30] Stopping HP IO Monitor
05/04/09 8:25:59 com.apple.SystemStarter[30] kextunload: unload kext /System/Library/Extensions/Pvsnet.kext succeeded
05/04/09 8:25:59 com.apple.SystemStarter[30] kextunload: unload kext /System/Library/Extensions/ConnectUSB.kext succeeded
05/04/09 8:26:02 com.apple.SystemStarter[30] kextunload: unload kext /System/Library/Extensions/vmmain.kext succeeded
05/04/09 8:26:02 com.apple.SystemStarter[30] kextunload: unload kext /System/Library/Extensions/hypervisor.kext succeeded
05/04/09 8:26:35 com.apple.launchctl.System[2] BootCacheControl: could not open /var/db/BootCache.playlist: No such file or directory
05/04/09 8:26:35 com.apple.launchctl.System[2] BootCacheControl: could not unlink playlist /var/db/BootCache.playlist: Unknown error: -1
05/04/09 8:26:37 com.apple.launchctl.System[2] launchctl: Please convert the following to launchd: /etc/mach_init.d/dashboardadvisoryd.plist
05/04/09 8:26:37 com.apple.launchd[1] (com.apple.blued) Unknown key for boolean: EnableTransactions
05/04/09 8:26:37 com.apple.launchd[1] (org.cups.cupsd) Unknown key: SHAuthorizationRight
05/04/09 8:26:37 com.apple.launchd[1] (org.ntp.ntpd) Unknown key: SHAuthorizationRight
05/04/09 8:26:49 org.ntp.ntpd[27] Error : nodename nor servname provided, or not known
05/04/09 8:26:57 com.apple.SystemStarter[30] Starting up Missing Sync Listener
05/04/09 8:26:57 com.apple.SystemStarter[30] Starting HP IO Monitor
05/04/09 8:26:58 com.apple.SystemStarter[30] kextload: extension /System/Library/Extensions/hypervisor.kext is already loaded
05/04/09 8:26:58 com.apple.SystemStarter[30] Starting HP Trap Monitor
05/04/09 8:26:58 com.apple.SystemStarter[30] kextload: extension /System/Library/Extensions/vmmain.kext is already loaded
05/04/09 8:26:59 com.apple.SystemStarter[30] kextload: extension /System/Library/Extensions/ConnectUSB.kext is already loaded
05/04/09 8:27:00 com.apple.SystemStarter[30] kextload: extension /System/Library/Extensions/Pvsnet.kext is already loaded
05/04/09 8:27:00 com.apple.SystemStarter[30] kextload: /Library/StartupItems/Parallels/Pvsvnic.kext loaded successfully
05/04/09 8:27:06 com.apple.SystemStarter[30] Sun Apr 5 08:27:06 wslys-Mac.local Missing Sync Listener[77] <Warning>: 3891612: (CGSLookupServerRootPort) Untrusted apps are not allowed to connect to or launch Window Server before login.
05/04/09 8:27:06 com.apple.SystemStarter[30] Sun Apr 5 08:27:06 wslys-Mac.local Missing Sync Listener[77] <Error>: kCGErrorRangeCheck : On-demand launch of the Window Server is allowed for root user only.
05/04/09 8:27:06 com.apple.SystemStarter[30] Sun Apr 5 08:27:06 wslys-Mac.local Missing Sync Listener[77] <Error>: kCGErrorRangeCheck : Set a breakpoint at CGErrorBreakpoint() to catch errors as they are returned
05/04/09 8:27:08 com.apple.SystemStarter[30] _RegisterApplication(), FAILED TO establish the default connection to the WindowServer, _CGSDefaultConnection() is NULL.
05/04/09 8:27:20 com.apple.launchd[1] (com.apple.UserEventAgent-LoginWindow[123]) Exited: Terminated
05/04/09 8:27:20 com.apple.launchctl.Aqua[129] launchctl: Please convert the following to launchd: /etc/machinit_peruser.d/RemoteUI.plist
05/04/09 8:27:20 com.apple.launchd[116] (com.apple.AirPortBaseStationAgent) Unknown key for boolean: EnableTransactions
05/04/09 8:27:21 com.apple.FolderActions.enabled[130] launchctl: Error unloading: com.apple.FolderActions.folders
05/04/09 8:27:42 quicklookd[146] [QL ERROR] 'Creating thumbnail' timed out for '<QLThumbnailRequest /Users/wsly/Downloads/m090374535329zdwg_650ref.mov>'
05/04/09 8:27:42 Dock[138] [QL ERROR] quicklookd crashed while thumbnailing /Users/wsly/Downloads/m090374535329zdwg_hdref.mov
05/04/09 8:29:52 com.apple.launchd[1] (com.apple.aslmanager[218]) Exited abnormally: Segmentation fault

Try repairing the disk through the Mac OS X install disk.

Can you please help to understand how the firefox decides on the Expires date for a cached javascript file ( my server did not set any Expire header, but firebox set it down).

# Question
Can you please help to understand how the firefox decides on the Expires date for a cached javascript file ( my server did not set any Expire header, but firebox set it down). I tried to understand but different javascript file gets different Expires date value when it is being cached. Please help me as I tried lot and could not get proper answer for this. Thanks in Advance.

Try posting at the Web Development / Standards Evangelism forum at MozillaZine. The helpers over there are more knowledgeable about web page development issues with Firefox. <br />
http://forums.mozillazine.org/viewforum.php?f=25 <br />
You'll need to register and login to be able to post in that forum.

Understanding of Explain plan

Hi all,
Could you please provide me any article on how to read and understand the complete explain plan by step by step?
I am not much familiar with expalin paln.
Wolud be appreciated your help !!
Regards,
Vissu...
Edited by: vissu on Aug 10, 2010 2:13 AM

[ | http://www.lmgtfy.com/?q=Understanding+explain+plans+in+oracle+10g]
[| http://download.oracle.com/docs/cd/B19306_01/server.102/b14211/ex_plan.htm]

Understand an explain plan

Hi,
following is the explain plan for my query :
Plan Table
| Operation                 | Name              | Rows | Bytes| Cost | Pstart| Pstop |
| SELECT STATEMENT          |                    |     1 | 139 |    464 |       |       |
| SORT GROUP BY            |                    |     1 | 139 |    464 |       |       |
|   NESTED LOOPS            |                    |     1 | 139 |    453 |       |       |
|    HASH JOIN              |                    |   352 |   35K|    277 |       |       |
|     NESTED LOOPS          |                    |   105 |    7K|     54 |       |       |
|      TABLE ACCESS BY INDEX|PS_CE_ITEMVAR_TMP   |   101 |    5K|     53 |       |       |
|       INDEX RANGE SCAN    |PS_C_ITEMVAR_TMP    |   101 |      |      5 |       |       |
|      INDEX UNIQUE SCAN    |PS_ITEMS_INV        |    14K| 244K|        |       |       |
|     TABLE ACCESS FULL     |PS_OUTPUT_LIST      |    47K|    1M|    222 |       |       |
Plan Table
|    TABLE ACCESS BY INDEX R|PS_SF_PRDNID_HEADR |    31K|    1M|      1 |       |       |
|     INDEX UNIQUE SCAN     |PS_SF_PRDNID_HEADR |    31K|      |        |       |       |
------------------------------------------------------------------------------------------How to understand it ? How to interpret it ?
Does this explain plan suggest you any tuning or any idea ?
Many thanks.

Can you check if you can avoid full table scan of this table - PS_OUTPUT_LIST
How to understand it ? How to interpret it ?Here is the rule.
1) First goto the inner most line. That will be the first one to get executed/accessed
Note : If two are two lines that are the same innermost level, then the one that is above it will get accessed first.
Here is the order for your case in sequence
1) INDEX RANGE SCAN |PS_C_ITEMVAR_TMP
2) TABLE ACCESS BY INDEX|PS_CE_ITEMVAR_TMP (a)
3) INDEX UNIQUE SCAN - PS_ITEMS_INV (b)
4) a and b will be joined to form a rowset - (c)
5) TABLE ACCESS FULL |PS_OUTPUT_LIST - (d)
6) c and d will have NESTED LOOPS ..
So on...
Please read the 9i or 10g Performance Tuning guide - that has the same explanation in the initial chapters
Message was edited by:
Srinivas.R

Can someone please help me understand this

I am a new poster here and was hoping someone might be able to help me...
I am writing a program that is supposed to generate a non applet (IE text) version of a 4-way intersection....however i have run into a problem that i simply cannot see a solution....please tell me why this code does not do what it is supposed to:
in i meant to call the car arrives method which is supposed to enqueue based on some randomly determined parameters, known as direction and bound....it is supposed to loop through and do that for every car created.. what i think is happnening is that everything is getting overwritten rather than enqueued...what i dont understand is why...the reason i believe that nothing is enqueuing is because later in the code i attempt to dequeue these queues and and set a paramter and i get a null pointer exception
PLEASE NOTE I RECIEVED THESE ERRORS BEFORE INSTANTIATING THE VEHICLE CURRENT CAR AS NULL...perhaps it is an instantiation problem but i cannot tell...please help me out as I have worked on this forthe last few days and am desparate for an answer
Vehicle CurrentCar = null;
     do
          //this ensures that the number of vehicles generated is within the spec guidelines
          if (j == 1)//might need to be changed
               numCars = generator.nextInt(7) + 4;
          else if ((j%2) == 0)
               numCars = generator.nextInt(6) + 10;
          else if ((j>1)&&( (j%2) !=0))
               numCars = generator.nextInt(4) + 10;
          totalCars += numCars;
          System.out.println("j is " + j);
          System.out.println( numCars);
          System.out.println(totalCars);
          //this ensures the number of vehicles never goes over 100
               if (totalCars>100)
                    int subCars = (totalCars - 100); //ensures that car total never goes above 100
                    numCars = numCars - subCars;
               //calls the MakeMeaCar method which contains the vehicle constructor
               for (int k=1;k <= numCars; k++)
               CurrentCar = MakeMeACar(count);
               count ++;
               Street.CarArrives(CurrentCar);
               CurrentCar.toString();
HERE IS THE CAR ARRIVES METHOD
public static void CarArrives (Vehicle CurrentCar)
//These if-else statements evaluate the enum parameters from the vehicle class and assigns them to a queue based on those parameters
if (CurrentCar.getDirection() == Directenum.s)
     if ((CurrentCar.getBound() == Boundenum.nB) || (CurrentCar.getBound() == Boundenum.wB))
          lfstrChurchNorthbound.enqueue(CurrentCar);
     else if (CurrentCar.getBound() == Boundenum.eB)
          rChurchNorthbound.enqueue(CurrentCar);
else if (CurrentCar.getDirection() == Directenum.n)
     if ((CurrentCar.getBound() == Boundenum.sB) || (CurrentCar.getBound() == Boundenum.eB))
          lfstrChurchSouthbound.enqueue(CurrentCar);
     else if (CurrentCar.getBound() == Boundenum.wB)
          rChurchSouthbound.enqueue(CurrentCar);
else if (CurrentCar.getDirection() == Directenum.e)
     if ((CurrentCar.getBound() == Boundenum.wB) || (CurrentCar.getBound() == Boundenum.sB))
          lfstrMainEastbound.enqueue(CurrentCar);
     else if (CurrentCar.getBound() == Boundenum.nB)
          rMainEastbound.enqueue(CurrentCar);
else if (CurrentCar.getDirection() == Directenum.w)
     if ((CurrentCar.getBound() == Boundenum.eB) || (CurrentCar.getBound() == Boundenum.nB))
          lfstrMainWestbound.enqueue(CurrentCar);
     else if (CurrentCar.getBound() == Boundenum.sB)
          rMainWestbound.enqueue(CurrentCar);
if you need more code to help please let me know...i would post it all but it about 8 pages or more total (inlcuding the various classes)
thanks
I appreciate all help given

ok running it through a debugger DID NOT HELP at all, please somebody help me, im very desparate now. i have spent 15 hours on this problem alone. i see absolutley nothing wrong with my code and have tried about 10 doifferent ways of trying this.,....i cannot get it to work, somebody please help me, ...in addition i was hoping someone could clear up an issue i have with enums...i do not understand how i can access the variable of the enum, the only access to it my text book provides is how to acess the string associated with enums....but i need to access the variable itself...how would i design such a get method....ive tried that a bunch of different ways as well, and right now im so lost that i want to cry, somebody please help, im begging on my knees...i really need someone to explain this to me....

Can someone please help me understand this? About Apple Repairs

Hello everyone,
I bought my macbook in Nov. 2009 in USA. I just moved to India and I've noticed the rubber base coming off and the infamous apple hairline crack. When I first took it to the India center, they kept insisting I had to pay for repair, I have a 1 year limited warranty.
Upon my insisting that they check with Apple USA first, they decided to call them and then asked me to send them pictures. I've sent the pictures, my repairs have been approved.
Now they tell me that I need to bring in the laptop and they need to run some software test for the crack, then they will submit this test and get the screen in about 4-5 days and then return the mac to me.
I need to understand this from people that have gone through this sort of repair. Why do they need to do a software test for a hardware issue?
Even if they have to do this software test, why can't they wait till the screen arrives (as this is the only way they claim to fix the crack) and then do the test all at once in one single day, rather than making me run back and forth with my macbook?
I also requested for them to forward Apple's response to me, they refused and said its internal.
I would really appreciate it if someone can please explain this to me, as the logic is just not making sense in my head. Maybe this is the way they do repairs and I'm not aware of them.. don't know..
Thanks everyone!!

ok running it through a debugger DID NOT HELP at all, please somebody help me, im very desparate now. i have spent 15 hours on this problem alone. i see absolutley nothing wrong with my code and have tried about 10 doifferent ways of trying this.,....i cannot get it to work, somebody please help me, ...in addition i was hoping someone could clear up an issue i have with enums...i do not understand how i can access the variable of the enum, the only access to it my text book provides is how to acess the string associated with enums....but i need to access the variable itself...how would i design such a get method....ive tried that a bunch of different ways as well, and right now im so lost that i want to cry, somebody please help, im begging on my knees...i really need someone to explain this to me....

10g Explain Plan ?

First off I am mostly an end user, just write queries and execute them, I have done very little administration under Oracel databases, besides the 10g Express edition, I have never installed anything else form oracle.
My company recently upgraded from 9i to 10g, and I am noticing that the cost is almost double vs. the old 9i db, using the same exact query and I am also noticing some new things in the explain plan. I use TOAD for my connection to the database at work and to view Explain plans.
Here is one of the explain plans: I wanted to learn what some of this new terminology means, like what is: (I've replaced the real schemas with the word schema, and tables with Table).
What is PX ?
PX COORDINATOR ?
Plan
CREATE TABLE STATEMENT ALL_ROWSCost: 15,471 Bytes: 126,893,988 Cardinality: 2,440,269
     9 LOAD AS SELECT Schema.Table
          8 PX COORDINATOR
               7 PX SEND QC (RANDOM) SYS.:TQ10001 Cost: 15,339 Bytes: 126,893,988 Cardinality: 2,440,269
                    6 SORT GROUP BY Cost: 15,339 Bytes: 126,893,988 Cardinality: 2,440,269
                         5 PX RECEIVE Cost: 15,339 Bytes: 126,893,988 Cardinality: 2,440,269
                              4 PX SEND HASH SYS.:TQ10000 Cost: 15,339 Bytes: 126,893,988 Cardinality: 2,440,269
                                   3 SORT GROUP BY Cost: 15,339 Bytes: 126,893,988 Cardinality: 2,440,269
                                        2 PX BLOCK ITERATOR Cost: 15,331 Bytes: 126,893,988 Cardinality: 2,440,269 Partition #: 8 Partitions accessed #1 - #16
                                             1 TABLE ACCESS FULL TABLE schema.Table2 Cost: 15,331 Bytes: 126,893,988 Cardinality: 2,440,269 Partition #: 8 Partitions accessed #1 - #16

PX = Parallel eXecution: query is executed on multiple processors. This may result from parameter changes and/or new defaults.
Using Parallel Execution, one session (your original session) coordinates the various extra processes.
Sybrand Bakker
Senior Oracle DBA

[8i] Can someone help me on using explain plan, tkprof, etc.?

I am trying to follow the instructions at When your query takes too long ...
I am trying to figure out why a simple query takes so long.
The query is:
SELECT COUNT(*) AS tot_rows FROM my_table;It takes a good 5 minutes or so to run (best case), and the result is around 22 million (total rows).
My generic username does not (evidently) allow access to PLAN_TABLE, so I had to log on as SYSTEM to run explain plan. In SQL*Plus, I typed in:
explain plan for (SELECT COUNT(*) AS tot_rows FROM my_table);and the response was "Explained."
Isn't this supposed to give me some sort of output, or am I missing something?
Then, the next step in the post I linked is to use tkprof. I see that it says it will output a file to a path specified in a parameter. The only problem is, I don't have access to the db's server. I am working remotely, and do not have any way to remotely (or directly) access the db server. Is there any way to have the file output to my local machine, or am I just S.O.L.?

SomeoneElse used "create table as" (CTAS), wich automatically gathers the stats. You can see the differende before and after stats clearly in this example.
This is the script:
drop table ttemp;
create table ttemp (object_id number not null, owner varchar2(30), object_name varchar2(200));
alter table ttemp add constraint ttemp_pk primary key (object_id);
insert into ttemp
select object_id, owner, object_name
from dba_objects
where object_id is not null;
set autotrace on
select count(*) from ttemp;
exec dbms_stats.gather_table_stats('PROD','TTEMP');
select count(*) from ttemp;And the result:
Table dropped.
Table created.
Table altered.
46888 rows created.
COUNT(*)
     46888
1 row selected.
Execution Plan
           SELECT STATEMENT Optimizer Mode=CHOOSE
   1         SORT AGGREGATE
   2    1      TABLE ACCESS FULL PROD.TTEMP
Statistics
          1 recursive calls
          1 db block gets
        252 consistent gets
          0 physical reads
        120 redo size
          0 PX remote messages sent
          0 PX remote messages recv'd
          0 buffer is pinned count
          0 workarea memory allocated
          4 workarea executions - optimal
          1 rows processed
PL/SQL procedure successfully completed.
COUNT(*)
     46888
1 row selected.
Execution Plan
           SELECT STATEMENT Optimizer Mode=CHOOSE (Cost=4 Card=1)
   1         SORT AGGREGATE (Card=1)
   2    1      INDEX FAST FULL SCAN PROD.TTEMP_PK (Cost=4 Card=46 K)
Statistics
          1 recursive calls
          2 db block gets
        328 consistent gets
          0 physical reads
       8856 redo size
          0 PX remote messages sent
          0 PX remote messages recv'd
          0 buffer is pinned count
          0 workarea memory allocated
          4 workarea executions - optimal
          1 rows processed

Lightroom 5.2 won't open after "successfully installed" - can anybody please help me understand why?

Hi everyone
I've bought and downloaded Adobe Lightroom 5 for a new iMac 27" intel core 5 3,4 GHz. The machine is only three days old and no more updates are to be found when searching for it. However; after the message that "lightroom 5 has successfully been installed" I don't get to open the program. So I never get to the point where I can register the serial number / registration key for purchased product.
I've followed the instructions that comes with Lightroom 5, but no luck. Also tried to uninstall and reinstall.
No secret that I'm total incompetent when it comes to understanding of computers and software....
Hope someone can help me understand what I'm doing wrong, and sugest some good solutions :-)
Thx

I think you may need to uninstall and then start over. There is no installer on the Mac for Lightroom so select it in Applications and send it to the trash. I suggest you download again from a different source. You can use the link below to download the free trial and then validate the software after installation with your product serial number. Ensure you choose your language version and MAC platform from the dropdown list at the top of the page.
After you click download it starts by downloading or updating (replace) the Adobe Download Assistant. You then browse the products and select Photoshop Lightroom 5 to start the installation.
https://www.adobe.com/cfusion/tdrc/index.cfm?product=photoshop_lightroom&promoid&promoid=D TEML

I wonder if it is possible to hack the iphone. because a friend received a bad message me and I never send the messenger .. Is someone please help me understand?

I wonder if it is possible to hack the iphone? because a friend received a bad message me and i never send the messenger. is someone please help me

It wasn't your iPhone that was hacked, but your email account (or
messaging account) that was hacked. Immediately change all your
passwords for such accounts.

HT5395 I have a mac , but i have no idea what version it is.. its all white and i just got it .. i have one problem , i have no idea how to send the text messages ? it keeps telling me i need to have some aol account .so somebody please help me understand

im just trying to find out how to send a message on the mac ...... someone please help ! thanks so much !

HI,
This is fairly generic (for iChat 4) although some links are out of date.
Start at the second menu down that says "Get a Screen Name"
http://www.ralphjohns.co.uk/versions/ichatvers4/howtos4.html
iChat 5 is virtually no different
iChat 6 adds the Yahoo option.
As has been said more specific info from yourself will enable a much more detailed reponse from us.
10:44 pm Wednesday; July 24, 2013
 iMac 2.5Ghz 5i 2011 (Mountain Lion 10.8.4)
 G4/1GhzDual MDD (Leopard 10.5.8)
 MacBookPro 2Gb (Snow Leopard 10.6.8)
 Mac OS X (10.6.8),
 Couple of iPhones and an iPad
"Limit the Logs to the Bits above Binary Images."  No, Seriously

Please help to understand 10g explain plan

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