Index Organized Table getting slow over time

Hello,
I recently discovered a problem in our our production environment:
We use an IOT to store search results in the form of primary keys (and additional data). This results in an excessive amount of INSERTs and DELETEs (the application is mainly a research tool). After some time, some statements on the IOT like SELECT COUNT(*) (optimizer using INDEX FAST FULL SCAN) take longer and longer, however the IOT index is used correctly by the optimizer and SELECTs which specify WHERE primk... (optimizer using INDEX RANGE SCAN) are executed with best performance.
It seems that the IOT somehow gets fragmented or unbalanced. Now my question ist, what's would be the best approach against that problem.
Would a daily ALTER TABLE ... MOVE ONLINE; be a good solution for example? Is this common practice with high volatile IOTs in 24x7 production environments?
Are there any better solutions for storing temporary search results?
Looking forward for your comments.
-sd

In addition to above mentioning...
Have you verified the distribution of IOT?
Like "ANALYZE INDEX .... VALIDATE STRUCTURE"? or "DBMS_STATS.GATHER_TABLE_STATS"?
It's natural that your full table scan(index fast full scan) gets slower in case that your IOT is getting bigger.
If you have lots of free leaf nodes, moving index will be beneficial although moving itself should be abvoided on busy time.
You also need to do sql trace and tkprof to measure how much workload your IOT is making.

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IMac link to 2Wire gateway gets slower over time

Hi All,
For the last couple of months I've had a situation where the airport signal drops off (and my download speed drops accordingly). When I start up I get "5 bars" from the wireless router. Then speed will drop, or pages fail to load, and I notice that Im getting just 1 or 2 bars. If I turn Airport off, then back on, it comes back at full strength and works for a while. The DSL router is a 2wire (ATT) that otherwise seems to work fine. I don't see much that I can adjust or configure with Airport or the IMac. The router is not too far away as the crow flies, but its a floor below. My mac mini and the wifes laptop seem pretty good. What can interfere with the signal. Also is the 801.1x security only, or something that yields stronger connections? THe online help for setting up the 801 in Airport was clear as mud. Suggestions? Thanks!

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Why Index-organized Table (IOT) is so slow during bulk/initial insert?

Tested in 11.1.0.7.0 RAC on RHEL 5 with ASM and 16KB block size.
Table is not wide: PK contains 4 columns and the leading 2 are compressed because they have relatively low cardinality; 2 other columns are included; the table contains another 4 audit columns; overflow table space defined.
Created 2 tables, one is IOT, the other is a normal heap-organized table with "COMPRESS FOR ALL OPERATIONS". Both tables have been range partitioned by the first column into 8 partitions, and DOP is set to 8.
Initial load volume is about 160M rows. Direct Path insert is used with parallel degree 8.
After initial load, create PK for the 4 columns with the leading 2 compressed on the normal table. The IOT occupied about 7GB storage; the normal table occupied 9GB storage (avg_row_len = 80 bytes) and the PK occupied 5.8GB storage.
The storage saving of IOT is significant, but it took about 60 minutes to load the IOT, while it only took 10 minutes to load the heap-organized table and then 6 minutes to create the PK. Overall, the bulk insert for IOT is about 4 times slower than the equivalent heap-organized table.
I have ordered the 4 columns in PK for the best compression ratio (lower cardinality comes first) and only compress the most repetitive leading columns (this matches ORACLE's recommendation in index_stats after validate structure), partition is used to reduce contention, parallel degree is amble, /*+ append */ is used for insert, the ASM system is backed with high-end SAN with a lot of I/O bandwidth.
So it seems that such table is good candidate for IOT and I've tried a few tricks to get the best out of IOT, but the insert performance is quite disappointing. Please advise me if I missed anything, or you have some tips to share.
Thanks a lot.
CREATE TABLE IOT_IS_SLOW
GROUP_ID      NUMBER(2)                   NOT NULL,
BATCH_ID      NUMBER(4)                  NOT NULL,
KEY1              NUMBER(10)                    NOT NULL,
KEY2              NUMBER(10)                NOT NULL,
STATUS_ID         NUMBER(2)                   NOT NULL,
VERSION           NUMBER(10),
SRC_LAST_UPDATED      DATE,
SRC_CREATION_DATE     DATE,
DW_LAST_UPDATED   DATE,
DW_CREATION_DATE DATE,
CONSTRAINT PK_IOT_IS_SLOW
PRIMARY KEY (GROUP_ID, BATCH_ID, KEY1, KEY2)
ORGANIZATION INDEX COMPRESS 2
INCLUDING VERSION
NOLOGGING
PCTFREE 20
OVERFLOW
PARALLEL ( DEGREE 8 )
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     PARTITION P02 VALUES LESS THAN (3),
     PARTITION P03 VALUES LESS THAN (4),
     PARTITION P04 VALUES LESS THAN (5),
     PARTITION P05 VALUES LESS THAN (6),
     PARTITION P06 VALUES LESS THAN (7),
     PARTITION P07 VALUES LESS THAN (8),
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);Even if /*+ APPEND */ is ignored for IOT, it is too slow, isn't it?

David_Aldridge wrote:
oftengo wrote:
>
Direct-path INSERT into a single partition of an index-organized table (IOT), or into a partitioned IOT with only one partition, will be done serially, even if the IOT was created in parallel mode or you specify the APPEND or APPEND_VALUES hint. However, direct-path INSERT operations into a partitioned IOT will honor parallel mode as long as the partition-extended name is not used and the IOT has more than one partition.
>
http://download.oracle.com/docs/cd/E11882_01/server.112/e17118/statements_9014.htm
Hmmm, that's very interesting. I'm still a bit cynical though -- in order for direct path to work on an index organized table by appending blocks I would think that some extra conditions would have to be satisfied:
* the table would have to be empty, or the lowest-sorting row of the new data would have to be higher than the highest-sorting row of the existing data
* the data would have to be sorted
... that sort of thing. Maybe I'm suffering a failure of imagination though.Could be. From a Tanel Poder post:
>
The “direct path loader” (KCBL) module is used for performing direct path IO in Oracle, such as direct path segment scans and reading/writing spilled over workareas in temporary tablespace. Direct path IO is used whenever you see “direct path read/write*” wait events reported in your session. This means that IOs aren’t done from/to buffer cache, but from/to PGA directly, bypassing the buffer cache.
This KCBL module tries to dynamically scale up the number of asynch IO descriptors (AIO descriptors are the OS kernel structures, which keep track of asynch IO requests) to match the number of direct path IO slots a process uses. In other words, if the PGA workarea and/or spilled-over hash area in temp tablespace gets larger, Oracle also scales up the number of direct IO slots. Direct IO slots are PGA memory structures helping to do direct IO between files and PGA.
>
So I'm reading into this that somehow these temp segments handle it, perhaps because with parallelism you have to be able to deal anyway. I speculate the data is inserted past the high water mark, then any ordering issues left can be resolved before moving the high water mark(s). Maybe examining where segments wind up in the data files can show how this works.
>
I can't find anything in the documentation that speaks to this, so I wonder whether the docs are really talking about a form of conventional path parallel insert into an IOT and not true direct path inserts.
One way to check, I think, would be to get the wait events for the insert and see whether the writes are direct.

Index Organized Tables

what is logical rowid in IOT?are they stored somwhere physically just like physical rowId's
what are secondary indexes?
what it means by leaf block splits?when and how it happens?
and the primary key constraint for an index-organized table cannot be dropped, deferred, or disabled,,,,,Is it true,,,,,if Yes Then Y
how does overflow works?how the two clauses are implemented PCTTHRESHOLD and INCLUDING.how they work?
Edited by: Juhi on Oct 22, 2008 1:09 PM

I'm sort-of tempted to just point you in the direction of the official documentation (the concepts guide would be a start. See http://download.oracle.com/docs/cd/B28359_01/server.111/b28318/schema.htm#sthref759)
But I would say one or two other things.
First, physical rowids are not stored physically. I don't know why you'd think they were. The ROWID data type can certainly be used to store a rowid if you choose to do so, but if you do something like 'select rowid from scott.emp', for example, you'll see rowids that are generated on-the-fly. ROWID is a pseudo-column, not physically stored anywhere, but computed whenever needed.
The difference between a physical rowid and a logical one used with IOTs comes down to a bit of relational database theory. It is a cast-iron rule of relational databases that a row, once inserted into a table, must never move. That is, the rowid it is assigned at the moment of its first insertion, must be the rowid it 'holds onto' for ever and ever. If you ever want to change the rowids assigned to rows in an ordinary table, you have to export them, truncate the table and then re-insert them: fresh insert, fresh rowid. (Oracle bends this rule for various maintenance and management purposes, whereby 'enable row movement' permits rows to move within a table, but the general case still applies mostly).
That rule is obviously hopeless for index structures. Were it true, an index entry for 'Bob' who gets updated to 'Robert' would find itself next to entries for 'Adam' and 'Charlie', even though it now has an 'R' value. Effectively, a 'b' "row" in an index must be allowed to "move" to an 'r' sort of block if that's the sort of update that takes place. (In practice, an update to an index entry consists of performing a delete followed by a re-insert, but the physicalities don't change the principle: "rows" in an index must be allowed to move if their value changes; rows in a table don't move, whatever happens to their values)
An IOT is, at the end of the day, simply an index with a lot more columns in it than a "normal" index would have -so it, too, has to allow its entires (its 'rows', if you like) to move. Therefore, an IOT cannot use a standard ROWID, which is assigned once and forever. Instead, it has to use something which takes account of the fact that its rows might wander. That is the logical rowid. It's no more "physical" than a physical rowid -neither are physically stored anywhere. But a 'physical' rowid is invariant; a logical one is not. The logical one is actually constructed in part from the primary key of the IOT -and that's the main reason why you cannot ever get rid of the primary key constraint on the IOT. Being allowed to do so would equate to allowing you to destroy the one organising principle for its contents that an IOT possesses.
(See the section entitled "The ROWID Pseudocolumn" and following on this page: http://download.oracle.com/docs/cd/B28359_01/server.111/b28318/datatype.htm#CNCPT1845
So IOTs have their data stored in them in primary key order. But they don't just contain the primary key, but every other column in the 'table definition' too. Therefore, just like with an ordinary table, you might want sometimes to search for data on columns which are NOT part of the primary key -and in that case, you might well want these non-primary key columns to be indexed. Therefore, you will create ordinary indexes on these columns -at this point, you're creating an index on an index, really, but that's a side issue, too! These extra indexes are called 'secondary indexes', simply because they are 'subsidiary indexes' to the main one, which is the "table" itself arranged in primary key order.
Finally, a leaf block split is simply what happens when you have to make room for new data in an index block which is already packed to the rafters with existing data. Imagine an index block can only contain four entries, for example. You fill it with entries for Adam, Bob, Charlie, David. You now insert a new record for 'Brian'. If this was a table, you could throw Brian into any new block you like: data in a table has no positional significance. But entries in an index MUST have positional significance: you can't just throw Brian in amongst the middle of a lot of Roberts, Susans and Tanyas. Brian HAS to go in between the existing entires for Bob and Charlie. Yet you can't just put him in the middle of those two, because then you'd have five entries in a block, not four, which we imagined for the moment to be the maximum allowed. So what to do? What you do is: obtain a new, empty block. Move Charlie and David's entries into the new block. Now you have two blocks: Adam-Bob and Charlie-David. Each only has two entries, so each has two 'spaces' to accept new entries. Now you have room to add in the entry for Brian... and so you end up with Adam-Bob-Brian and Charlie-David.
The process of moving some index entries out of one block into a new one so that there's room to allow new entries to be inserted in the middle of existing ones is called a block split. They happen for other reasons, too, so this is just a gloss treatment of them, but they give you the basic idea. It's because of block splits that indexes (and hence IOTs) see their "rows" move: Charlie and David started in one block and ended up in a completely different block because of a new (and completely unrelated to them) insert.
Very finally, overflow is simply a way of splitting off data into a separate table segment that wouldn't sensibly be stored in the main IOT segment itself. Suppose you create an IOT containing four columns: one, a numeric sequence number; two, a varchar2(10); three, a varchar2(15); and four, a blob. Column 1 is the primary key.
The first three columns are small and relatively compact. The fourth column is a blob data type -so it could be storing entire DVD movies, multi-gigabyte-sized monsters. Do you really want your index segment (for that is what an IOT really is) to balloon to huge sizes every time you add a new row? Probably not. You probably want columns 1 to 3 stored in the IOT, but column 4 can be bumped off over to some segment on its own (the overflow segment, in fact), and a link (actually, a physical rowid pointer) can link from the one to the other. Left to its own devices, an IOT will chop off every column after the primary key one when a record which threatens to consume more than 50% of a block gets inserted. However, to keep the main IOT small and compact and yet still contain non-primary key data, you can alter these default settings. INCLUDE, for example, allows you to specify which last non-primary key column should be the point at which a record is divided between 'keep in IOT' and 'move out to overflow segment'. You might say 'INCLUDE COL3' in the earlier example, so that COL1, COL2 and COL3 stay in the IOT and only COL4 overflows. And PCTTHRESHOLD can be set to, say, 5 or 10 so that you try to ensure an IOT block always contains 10 to 20 records -instead of the 2 you'd end up with if the default 50% kicked in.

Heap tables and index organized tables

I performing migration from mssql server to oracle 10gr2 rdbms, in mssql all tables have clustered pk, index. Is it necessary to use index organized tables for that migration, or enough ordinal heap organized tables and what differences between those tables, and mssql tables
Thanx

In Oracle, the typical table is a standard 'heap' table. Stuff goes into the heap table randomly, and randomly comes out.
An Index Organizaed Tables is somewhat similar to a Cluster Index in SS. It can have some performance advantages over heap tables - when the heap table has an associated index on the primary key.
The IOT can also have some disadvantages, such as the need for an Overflow table to handle the extra data when a row doesn't conveniently fit in a block (implying multiple I/Os), and an extra translation table if bitmap indexes are required (implying extra I/Os).
An unintelligent developer will generally believe that Oracle and SQL Server are the same - after all they both run SQL - and will attempt to port by a simple translation of syntax.
An intelligent developer will test both styles of tables, during a port. Such a developer will also be quick to learn about the changes in internals (such as locking mechanisms) and will realize that different styles of coding are required for many application situations.
I recommend reading Tom Kyte's books to get handle on pros and cons as well as testing techniques to help a developer become intelligent.

Creation of context index on index-organized table

I encountered a problem when creating a domain index(intermediate text context index) on a index-organised table in oracle 8i.
The description of the error is stated below:
"ORA-29866: cannot create domain index on a column of index-organized table "
I have configured intermediate text properly and even it worked for those tables which are not index-organised(ordinary tables).
This problem has occured only when i made the tables as index organised.
Please provide us a solution to this problem as early as possible.
In case if you require any more details i shall provide them.

Please ask questions about Oracle Text (formerly interMedia text) in the Oracle Text forum. You will get a quicker, more expert answer there.

Is ther a way to speed up a Mac? Mine has gotten slower and slower over time. When memory comes close to full would that have an effect on performance? Is there a way to determine unused programs/software to remove and free space?

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Start with visits to:     OS X Maintenance - MacAttorney;
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Boot into Safe Mode then repair your hard drive and permissions:
Repair the Hard Drive and Permissions Pre-Lion
Boot from your OS X Installer disc. After the installer loads select your language and click on the Continue button. When the menu bar appears select Disk Utility from the Utilities menu. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list. In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive. If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the installer.
Repair the Hard Drive - Lion/Mountain Lion/Mavericks
Boot to the Recovery HD:
Restart the computer and after the chime press and hold down the COMMAND and R keys until the Utilites Menu screen appears. Alternatively, restart the computer and after the chime press and hold down the OPTION key until the boot manager screen appears. Select the Recovery HD disk icon and click on the arrow button below.
When the recovery menu appears select Disk Utility. After DU loads select your hard drive entry (mfgr.'s ID and drive size) from the the left side list. In the DU status area you will see an entry for the S.M.A.R.T. status of the hard drive. If it does not say "Verified" then the hard drive is failing or failed. (SMART status is not reported on external Firewire or USB drives.) If the drive is "Verified" then select your OS X volume from the list on the left (sub-entry below the drive entry,) click on the First Aid tab, then click on the Repair Disk button. If DU reports any errors that have been fixed, then re-run Repair Disk until no errors are reported. If no errors are reported, then click on the Repair Permissions button. Wait until the operation completes, then quit DU and return to the main menu. Select Restart from the Apple menu.
Restart your computer normally and see if this has helped any. Next do some maintenance:
For situations Disk Utility cannot handle the best third-party utility is Disk Warrior; DW only fixes problems with the disk directory, but most disk problems are caused by directory corruption; Disk Warrior 4.x is now Intel Mac compatible.
Note: Alsoft ships DW on a bootable DVD that will startup Macs running Snow Leopard or earlier. It cannot start Macs that came with Lion or later pre-installed, however, DW will work on those models.
Suggestions for OS X Maintenance
OS X performs certain maintenance functions that are scheduled to occur on a daily, weekly, or monthly period. The maintenance scripts run in the early AM only if the computer is turned on 24/7 (no sleep.) If this isn't the case, then an excellent solution is to download and install a shareware utility such as Macaroni, JAW PseudoAnacron, or Anacron that will automate the maintenance activity regardless of whether the computer is turned off or asleep. Dependence upon third-party utilities to run the periodic maintenance scripts was significantly reduced since Tiger. These utilities have limited or no functionality with Snow Leopard or later and should not be installed.
OS X automatically defragments files less than 20 MBs in size, so unless you have a disk full of very large files there's little need for defragmenting the hard drive.
Helpful Links Regarding Malware Protection
An excellent link to read is Tom Reed's Mac Malware Guide.
Also, visit The XLab FAQs and read Detecting and avoiding malware and spyware.
See these Apple articles:
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          OS X Lion- Protect your Mac from malware
          OS X Mountain Lion- Protect your Mac from malware
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If you require anti-virus protection I recommend using VirusBarrier Express 1.1.6 or Dr.Web Light both from the App Store. They're both free, and since they're from the App Store, they won't destabilize the system. (Thank you to Thomas Reed for these recommendations.)
Troubleshooting Applications
I recommend downloading a utility such as TinkerTool System, OnyX, Mavericks Cache Cleaner, or Cocktail that you can use for removing old log files and archives, clearing caches, etc. Corrupted cache, log, or temporary files can cause application or OS X crashes as well as kernel panics.
If you have Snow Leopard or Leopard, then for similar repairs install the freeware utility Applejack. If you cannot start up in OS X, you may be able to start in single-user mode from which you can run Applejack to do a whole set of repair and maintenance routines from the command line. Note that AppleJack 1.5 is required for Leopard. AppleJack 1.6 is compatible with Snow Leopard. Applejack does not work with Lion and later.
Basic Backup
For some people Time Machine will be more than adequate. Time Machine is part of OS X. There are two components:
1. A Time Machine preferences panel as part of System Preferences;
2. A Time Machine application located in the Applications folder. It is
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    requires a backup drive that is at least twice the capacity of the
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Alternatively, get an external drive at least equal in size to the internal hard drive and make (and maintain) a bootable clone/backup. You can make a bootable clone using the Restore option of Disk Utility. You can also make and maintain clones with good backup software. My personal recommendations are (order is not significant):
1. Carbon Copy Cloner
2. Get Backup
3. Deja Vu
4. SuperDuper!
5. Synk Pro
6. Tri-Backup
Visit The XLab FAQs and read the FAQ on backup and restore. Also read How to Back Up and Restore Your Files. For help with using Time Machine visit Pondini's Time Machine FAQ for help with all things Time Machine.
Referenced software can be found at MacUpdate.
Additional Hints
Be sure you have an adequate amount of RAM installed for the number of applications you run concurrently. Be sure you leave a minimum of 10% of the hard drive's capacity as free space.
Add more RAM. If your computer has less than 2 GBs of RAM and you are using OS X Leopard or later, then you can do with more RAM. Snow Leopard and Lion work much better with 4 GBs of RAM than their system minimums. The more concurrent applications you tend to use the more RAM you should have.
Always maintain at least 15 GBs or 10% of your hard drive's capacity as free space, whichever is greater. OS X is frequently accessing your hard drive, so providing adequate free space will keep things from slowing down.
Check for applications that may be hogging the CPU:
Pre-Mavericks
Open Activity Monitor in the Utilities folder. Select All Processes from the Processes dropdown menu. Click twice on the CPU% column header to display in descending order. If you find a process using a large amount of CPU time (>=70,) then select the process and click on the Quit icon in the toolbar. Click on the Force Quit button to kill the process. See if that helps. Be sure to note the name of the runaway process so you can track down the cause of the problem.
Mavericks and later
Open Activity Monitor in the Utilities folder. Select All Processes from the View menu. Click on the CPU tab in the toolbar. Click twice on the CPU% column header to display in descending order. If you find a process using a large amount of CPU time (>=70,) then select the process and click on the Quit icon in the toolbar. Click on the Force Quit button to kill the process. See if that helps. Be sure to note the name of the runaway process so you can track down the cause of the problem.
Often this problem occurs because of a corrupted cache or preferences file or an attempt to write to a corrupted log file.

Problem with a 2 columns Range Partitioning for a indexed organized table

have an indexed organized table with a 2 column PK. the first field (datum) is a date field the second field (installatieid) is a number(2) field.
Every minute a 7 records are inserted (installatieid 0-6).
I like to partition this table with one partition per year per installatieid.
I tried to do it with:
partition by range(datum,installatieid)
(partition P_2004_0 values less than (to_date('2004-01,'yyyy-mm'),1)
,partition P_2004_6 values less than (to_date('2004-01','yyyy-mm'),7)
partition P_2005_0 values less than (to_date('2005-01','yyyy-mm'),1)
,partition P_2005_6 values less than (to_date('2005-01','yyyy-mm'),7)
but now only the P_2004_0 and P_2005_0 are filled.
I thought about to combine a range partition on datum with a list subpartition on installatieid, but I read this is not allowed with an index organized table.
How can I solve this problem.

partition by range(datum,installatieid)
(partition P_2004_0 values less than
(to_date('2004-01,'yyyy-mm'))
,partition P_2004_6 values less than
(to_date('2004-07','yyyy-mm'))
partition P_2005_0 values less than
(to_date('2005-01','yyyy-mm'))
,partition P_2005_6 values less than
(to_date('2005-07','yyyy-mm'))
? Sorry haven't got time to test it this morning ;0)

How to handle Index Organized Tables in schema capture?

I’m trying setup streams schema level between 2 database source 10.2.0.4 and 11g; one way streams;
The source has Index Organized Tables with column rowed; Oracle streams doesn’t support data type rowed;
Is it works around?
Thanks

At the moment, you can't do it declaratively. You have to do it in an event handler. Assuming you have the userid setup as a query parameter in the view object, something like this should get you started:
public EventResult handleEvent(
BajaContext context, Page page, PageEvent event) throws Throwable
HttpSession session = context.getServletRequest().getSession(true);
ViewObject view = ServletBindingUtils.getViewObject(context);
String userid = session.getAttribute("userid");
view.setWhereClauseParam(0, userid);
view.executeQuery();

Primary key constraint for index-organized tables or sorted hash cluster

We had a few tables dropped without using cascade constraints. Now when we try to recreate the table we get an error message stating that "name already used by an existing constraint". We cannot delete the constraint because it gives us an error "ORA-25188: cannot drop/disable/defer the primary key constraint for index-organized tables or sorted hash cluster" Is there some sort of way around this? What can be done to correct this problem?

What version of Oracle are you on?
And have you searched for the constraint to see what it's currently attached to?
select * from all_constraints where constraint_name = :NAME;

Data rate slows over time: Using Time Capsule (4th) and AirPort Express (1st)

Time Capsule using Airport Express to extend network.
Over 3-4 days my data rate gradually gets slower and slower until I have to reboot both TC and AE.
Fresh reboot gets me 10Mbs or better for a while and then slows over time to 2Mbs or less.
I can cable directly to the ISP modem, taking TC and AE out of the equation, and its smokin fast
No hair left to pull out, so any help or suggestions would be appreciated.
Time Capsule (4th gen) - Model A1409
Version - 7.6.4
Wireless Mode: Create a wireless network
Wireless Security: WPA2
Channel: 149 (Automatic), 11 (Automatic)
Allow this network to be extended is checked
Radio Mode: Automatic
Multicast Rate: Low
Transmit Power: 100%
Use wide channels is checked
Guest Network is NOT enabled
Mac Address Access Control: Not Enabled
Connection Sharing: Share a public address
Using DHCP
One printer attached to Time Capsule
Airport Express (1st gen) - Model A1143
Version 7.6.4
Wireless Mode: Extend a wireless network
Wireless Security: WPA2
Channel: 11 (Automatic)
Mac Address Access Control: Not Enabled
Using DHCP

You have your wireless channels on auto.. it is usually better to control it.
You will notice I have different names for 2.4ghz and 5ghz.. then I can force the link to either band.
After you set Radio Channel selection to Manual,, click edit. You can then set the channels.
Lock the channels.. ie you take control and you set what the wireless channels will be.. when you extend wireless this works far better. The auto channel system has to run on the Extender.. but since the main base is fixed on the 2.4ghz so it will be also.. the only channel that can flap around is 5ghz (extender) since that is not under my control. Of course it is up to you to determine which channel works best.. I strongly recommend the upper channels for 2.4ghz and the lower channels for 5ghz.
So.. I have set 5ghz to 48 on the main base.. and the auto channel sets it to 149 in the extender.
One strange thing results from my setup .. (amongst many!!)
You cannot name the wireless for 5ghz in the extender.. so in my case the upstairs wireless extender has both 2.4ghz and 5ghz named TC24ghz.. nought that I can do about it. But it is not a big deal.
You can see the result in the wireless diagnostics. The last wireless I have put in the box.. it is named TC24ghz but is in fact running on 5ghz. That is just how the over automated system of the apple routers work.. If I could I would fix it.. and maybe shall via serial console at a later date.

Creation of context index on index-organized tables

I encountered a problem when creating a domain index(intermediate text context index) on a index-organised table in oracle 8i.
The description of the error is stated below:
"ORA-29866: cannot create domain index on a column of index-organized table "
I have configured intermediate text properly and even it worked for those tables which are not index-organised(ordinary tables).
This problem has occured only when i made the tables as index organised.
Please provide us a solution to this problem as early as possible.
In case if you require any more details i shall provide them.

creation of domain indexes (such as context) on iot's
is not currently supported in oracle.

Finding Parent Table of Index Organized Table

I am using Oracle 10g Rel 2 and faced error message while granting select priviliges ORA-25191: cannot reference overflow table of an index-organized table
I searched solution and found: Issue the statement against the parent index-organized table containing the specified overflow table.
Question is how can i find parent index-organized table containing the specified overflow table.
Further i faced an other error while granting select priviliges : ORA-22812: cannot reference nested table column's storage table
Solution is same and i found parent table and first granted select priviliges on that parent table and then tried then tried to grant select priviliges on required table to public and did not worked.
if some body could help me!!!!!!!!!!!!!!!!!!!!!

And just what does this problem have to do with either the SQL and/or PL/SQL languages?
Try the [url http://forums.oracle.com/forums/forum.jspa?forumID=61&start=0]Community Discussion Forums » Database » Database - General forum.
Also suggest that you read up on just what an IOT is, and where and when overflows apply. See the [url http://download.oracle.com/docs/cd/B19306_01/server.102/b14220/schema.htm#sthref1060]Oracle® Database Concepts guide.

Indexes on Index Organized Table

I remember seeing a note regarding problems in using indexs on index organized tables. Of course, the index would be something other than the one implied in the table definition. I can't seem to remember what the problem was.
Has anyone used indexes on index organized tables successfully? (unsuccessfully?)
Oracle 8i on a Tru64 platform
Thanks
-dave

I remember seeing a note regarding problems in using indexs on index organized tables. Of course, the index would be something other than the one implied in the table definition. I can't seem to remember what the problem was.
Has anyone used indexes on index organized tables successfully? (unsuccessfully?)
Oracle 8i on a Tru64 platform
Thanks
-dave

Index Organized Table getting slow over time

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