Storing on DVD

If I download a bunch of TV shows from itunes, burn the files to a DVD and delete them from my computer to save space, and load them back to my computer when I want to watch that particular episode, should I run into any problems in terms of being able to watch it as many times as I want? I know you're allowed to watch songs on up to five computers and didn't know if this would create an issue if I tried to reload the video, delete it, and reload it more than five times.
Thanks!

Should work with no problems.

Similar Messages

Lightroom catalogs from images stored on DVD'S

I have hundreds of DVD disks that I want to Catalogue. I import the files using just the ADD function into a newly created collection, yet once he DVD is ejected the files loose their path.
I thought that files from external media did not have to exist on a hard drive to be catalogued. I used Portfolio before this adventure into Lightroom and I had nop problem at all.
I have studied tutorials and the only discussion within these lessons is about files on connected hard drives or RAID systems.
Any advice is welcome.
PD

HI,
Lr does not really support the workflow you want. You want to catalog dvd's with LR. So, if you eject the dvd the path in Lr will be your dvd rom. Not usefull.
You can try the following work around: import the dvd an use some of the metadata fields (exif, iptc or keywords) to store the name of your dvd in it. You can use the search inside Lr to find the contents of a dvd or you can brows your catalog, find an image and read the metadata to find out on which dvd the image is stored.
You can also use the collection feature and create a collection for every dvd.
It might be usefull to set the following cataloge settings: generate 1:1 previews and do not delete previews.

Photos stored in DVD-ROM section of DVD Slideshow

I have created a DVD Slideshow using 50 pictures from iphoto and I checked "Add image files to DVD-ROM" box. I have done this several years ago but am totally baffled as to to link these images to a button which will allow access to them from the finished DVD. HELP!
iMac G4 Mac OS X (10.4.7) 512 MB SDRAM, 800Mghz

Hi cputzi
You can do this w/in DVDSP.
Did you already check out the iDVD Help Menu Procedure?
To create a slideshow in iDVD:
1. Click Media to open the Media pane, then click Photos to display your iPhoto albums.
2. Drag an album to the DVD menu. A button is created that links to the images. The button has the name of your iPhoto album and automatically displays the first slide in the slideshow.
3. If you want to change the button label, select the button and type a new name.
4. Double-click the button to open the slideshow editor.
5. The slideshow editor shows thumbnails of the photos in the slideshow. Drag the slider to change the size of the thumbnails, so you can see more slides at once, or fewer slides with more detail.
6. Add, arrange, or delete slides from the slideshow to create the sequence you want.
• To add other images, drag files or folders from the Finder to the slideshow editor.
• To reorder the images, select the slides you want to move and drag them to a different position.
• To delete an image, select it and choose Edit > Delete.
7. Click Settings and select the settings you want for the slideshow:
• "Loop slideshow" makes the slideshow repeat continuously until the viewer moves to a different part of the DVD.
• "Display navigation arrows" shows navigation arrows on the screen to indicate where the viewer is in the slideshow.
• "Add image files to DVD-ROM" adds copies of the slideshow images to the DVD disc so viewers can download them to their computers.
• "Show titles and comments" lets you add titles and comments to your slideshow images that are visible in the slideshow.
8. Click the Transition pop-up menu and choose a transition to smoothly move from one image to the next.
9. Click the Slide Duration pop-up menu and choose the length of time you want each slide to stay on the screen. Be sure to allow enough time for the transition you selected.
10. To let the viewer advance through the slideshow manually using a remote control, choose Manual.
11. Note: If you're adding a soundtrack, you don't need to set the slide duration.
12. To add a soundtrack, click Media to open the Media pane, then click Audio to find a song in your iTunes library or GarageBand that would make a nice background for the slideshow.
13. Drag the song or audio track from the Media pane, or from another location on your hard disk, and drop it in the audio well in the slideshow editor.
14. iDVD automatically adjusts the overall duration of the slides to match the length of the audio clip. The slide duration is changed to "Fit to Audio." You can change the duration if you want.
15. Drag the "Slideshow volume" slider to set the volume. You can check the volume when you preview the slideshow.
Note: When you add RAW images from iPhoto, the RAW files will appear in the slideshow as JPEG images. The RAW files are placed in the DVD-ROM portion of the disc if you choose that option.
Hope this is helpful
SDMacuser

How can I save previews for old projects, while burning the project to DVD?

I'll admit, I haven't read the user manual cover to cover (or screen to screen for the electronic version), and haven't spent hours combing the discussions here, but I have searched for all the relevant keywords I can think of and can't find a concise answer to this question.
I get the basic idea of Vaults (I think), but haven't found much info about long term storage of projects. I'm fulltime freelance, but not super busy, and I can easily generate 100,000 images each year. I don't have the cash to be keeping all of these images in Aperture projects on external hard drives for eternity, and I'd be surprised if anyone else does. Good thing I'm not a medium format digital shooter producing 50GB each day huh?
I remember seeing a clip of a photographer 2 or 3 years ago discussing the differences between storing digital and film images. He was making the point that throwing away files you don't think you'll need again can be a mistake, citing a shot he had of Clinton and Lewinsky together, before Clinton and Lewinsky were news. "If I'd been shooting digital, that image wouldn't exist today". It was a great pic, and when that whoel scandal erupted, it made him alot of money.
So at present I'm storing every image I take in finished projects on DVD trusting that in the future I'll be looking for a shot of someone I may have shot 5, 10, 15 years ago.
I caught part of a discussion that talked about keeping the preview files for all the images (and subsequent versions) for each project. I'd love to be able to keep lo-res previews/copies of everything I've shot to date, and have them immediately accessible on my hard drive, while my full size projects are safely stored on DVD, taking up space on a bookshelf rather than on my hard drive. Loading 10 DVD's worth of projects to see what's inside them is a headache I'd like to avoid if possible, in favour of instantly checking out lo-res previews to look a shot up.
Is there an easy way to burn a completed project to DVD, but keep only the (lo res, lo size) previews on my hard drive?
20" iMac and G4 Powerbook Mac OS X (10.4.8) "A creative and dynamic professional" (I lie alot and can't sit still)

hello, kiwi
quote: "Is there an easy way to burn a completed project to DVD, but keep only the (lo res, lo size) previews on my hard drive?"
yes.
maybe,...
1. you might think of making DVD backups first prior to importing the photos into Aperture. "Store Files: In their current location" once in Aperture make low rez Previews, and export finished Project.
or,
2. bring in the photographs to hard drive first prior to importing the photos into Aperture. "Store Files: In their current location" once in Aperture make low rez Previews, and export finished Project.
the low rez Previews will stay in Aperture but the high quality Versions will be exported onto DVDs and gone from the hard drive (if you delete the originals).
another way would be to export small about 50-70 pixel wide high quality jpegs to a folder on your Desktop and import & keep these in Aperture Library as a reference. make metadata to show where the original Project DVDs are stored and DVD filing system used.
victor

Restore Hard Drive from Backup DVD's

Own 4 HP G7 Windows 7 system
one computer was showing the fan was overheating and requested to be turned off soon
turned it off
Took hard drive out of the unit A with the fan problems and swapped with the hardrive from
unit B (another G7)
Computer A or B would not boot properly
So I ran a HP backup of the Hard drive from A which is now in unit B requested 10 DVD's seems to have backuped with out problems but could only boot in safe mode
Took the unit A in for repair-Fan was dirty, they cleaned it, and it worked fine-exchanged hard drives back to origiinal state A with A and B with B
B started without a problem and was normal
A had problems and the tech said they need to reinstall opeating system to boot but would not damage data.
Opened B but it had no data. Used the DVD to restore but hung up on 2nd DVD at 4 % and said could not find hard drive (1st DVD was OK)
All 10 DVD have swm files so I took it to a data recovery repair shop. They said they can read and retrieve most files but when un zipped they were corrupted and could not be read.
Need the data for my son's college work stored.
DVD's seem to have data but can not retrieve or reload. Original haed drive in A seems to have been over written and data is no longer there but have DVD's the backup was with HP software onto DVD but can not retrive the files. Can HP retrieve the compressed files from the DVD's for a restore?
Seems that the units both G7's had different proceessors one was dual he other not and the backup was made while the hard drives were swapped out. Please advise as what can be done.

Hi @TonyBlair1 ,
Thank you for your inquiry, I will do my best to assist you!
Please remember when posting to include your exact model of G7 you have.
How Do I Find My Model Number or Product Number?
I grasp that you have 4, G7 notebooks running Windows 7. Computer A had a overheating issue and you removed the hard drive and swapped it with computer B.
Neither computer would boot properly.
So you ran a backup from A which is in computer B from safe mode.
You took unit A in and had it repaired.
You replaced drive A into computer A and drive B back in computer B.
B worked normally.
Now Drive A Computer A
The tech advised you that you need to reinstall Windows to boot but it would not affect your files. You attempted to use your DVDs to do a restore but on 2nd DVD you get an error no hard drive found.
First I would like to clarify, did you do a Microsoft backup and restore or did you do a HP recovery and backup?
As you did stated you used HP software I am providng links on recovery.
Using System Recovery, Factory Reset and Minimized Image Recovery Options
Performing an HP System Recovery (Windows 7)
Troubleshooting HP System Recovery Problems (Windows 7)
Restoring Files that were Backed Up Using HP Recovery Manager (Windows 7)
I hope this helps.
Sparkles1
I work on behalf of HP
Please click “Accept as Solution ” if you feel my post solved your issue, it will help others find the solution.
Click the “Kudos, Thumbs Up" on the bottom right to say “Thanks” for helping!

Backup photos to DVD (Not Time Machine)

Hi,
I am running Time Machine and backing up locally. What I am interested in doing is backing up my photos to DVDs and storing the DVDs off site. Is there any easy & free way to do that? I know I can make a burn folder and do it by hand. What I am looking for is a tool that I can choose a folder and select copy and it will automagically span the DVDs.
Thanks

Hi K J
If you have the images in iPhoto and select the album, and from the menu Share, select Burn, you can put them onto a DVD that way. I don't know if that is sufficiently automagical enough for you but that seems pretty direct to me.

DVD Project Backup

I was recently backing up a DVD project onto a data dvd. After the disc was finished burning, I opened the project file from the disc (my first mistake.) When I saw that the project opened, I thought all was well, that is until I went to the hard drive to delete the project. To my dismay, the folder where I stored my DVD projects, all of the files had been replaced with *.par files associated with the project I backed up and opened off the disc. NONE of the other files were in the folder and i have yet to be able to find them or unerase them. Does anyone have any suggestions as to why this happened, or more importantly how I could possibly get the files back?

PT and Lennart,
Thanks for your quick response. I've been burning DVDs of various types (data, video) for several years now, however, I've never had/needed to burn an iMovie project to a DVD (I would always archive them on another harddrive).
I'm helping a friend out, and he has 1 harddrive with very limited space. He has 6 unfinished iMovie projects, each about 15 minutes long. I figured W/6 DVDs he could free up about 18gb-24gb.
I wanted to make sure "project corruption" wouldn't be an issue.
Thanks again
eMAC Mac OS X (10.2.x)

Formating Failed DVD Studio Pro 4

I have been using DVD Studio Pro 4 for several months (having upgraded from previous version) and had no problems. Now regardless of build and format or burn and even going to image file I get 'Formating Failed' see log - log lists 'Formating Cancelled'.
The only recent change has been to replace a faulty HDD - the replaced HDD has nothing to do with the boot drive, where applications are stored - the DVD I am trying to create has been done several times from material not stored on the faulty or new replacement drive.
Any suggestions????
I came across a post from 2009 where someone descries a similar thing which seemd to just rectify itself.
Thanks

Try this: Go to File->Advanced Burn->Build and let DVD-SP do the build on a local hard drive. If that works, try burning the DVD from that build using Toast or Disc Utility: http://www.kenstone.net/fcp_homepage/making_dvd_copies.html
If the Build worked OK, the problem likely isn't in DVD-SP.
If the disc burn failed, it may be the media or the burner that is the source of the problem.
-DH

Put 180 min of VHS on DVD - DL disc or not?

I have a VHS tape with 180 mins of material that I want to put on a DVD+/-R.
Can I use DVD+R DL discs with DVDSP without a problem?
What resolution and bitrate do you suggest I should use?
I think using 720x576 and 4,5 mbit is very much overkill, and then the video won't fit on a 4,7 GB DVD-R.
I did a test with 352x576 at 3 mbit, and it did look OK, but that was more than two years ago...
Any suggestions much apprecieated.

As for the difference in resolution, VHS material stored on DVD-R is still 480 lines, regardless of what the native resolution was. It's like taking a photo of your screen with a digital camera -- sure, your screen is only 72dpi, but the resolution of the photo is determined by your camera's chip, not the resolution of the source.
A lot of people use the limited "resolution" of VHS as an excuse to use half-D1 resolution, but you often end up with sub-VHS video quality. Using the digital camera metaphor again, it doesn't matter if your screen resolution is only 640x480, if you take a photo of your screen with one of those cheapie 640x480 digital cameras, you won't get an image that's identical to the screen display, it will be visibly worse.
How can this be if the resolution of both the screen and the camera are both 640x480? Because the 640x480 resolution of the camera limits its capability to create a clear digital image of the analog world (pointing a camera at your screen isn't a digital transfer, even if you have a digital monitor). If you could plug a device into your monitor port that would extract a digital image from it, then yes, you could get a pixel-for-pixel representation of what was on your screen, but analog-to-digital doesn't work that way.
To understand the concept behind VHS-to-DVD transfers, it might help to look at it as a film-to-video transfer. Film does not really have a "resolution", strictly speaking. The grain of the film can limit image quality, but if you use the absolute minimum resolution to transfer film to tape, you won't get very good results. In the same way, you really need all 480 lines of an NTSC DVD for VHS transfers, and you don't really have the option of using less. You're essentially taking a picture of the signal from the tape -- it's not a line-for-line transfer.
For the same reason, cutting the horizontal resolution in half is the worst thing you could possibly do, since the horizontal lines in VHS or other analog formats isn't broken up into "pixels" as digital formats are. Therefore, using half of DVD's available 720-pixel horizontal resolution means you get an image that's only half as good as the picture you'd get using the full 720 pixels. If you had the capability to cut the number of lines in half so you only had 240, it would actually have less of an effect than using half-D1 resolution would. Unfortunately, that option is not available.
The bottom line is, if you go by the "resolution" figures of VHS to justify using less than the full 720x480 resolution of DVD, you're gonna end up less-than-VHS-quality. If you're okay with that, great -- it just blows a hole in the myth that simply transfering VHS content to DVD is an automatic improvement.

Blank DVD keeps ejecting?

Hello someone,
I am trying to load a blank DVD and it keeps getting spit back out at me after what sounds like the machine considering the DVD.
I have tried just unwrapped Maxll up to 4x DVD-R as well as Maxell up to 4x DVD-RW. With both, the machine offers the same response.
Any ideas of what could be wrong with user or machine under these circumstances?
Also, I need to store a 12 GB imovie folder onto seperate DVDs. I will need to be able to access this info and bring it back to an external FW drive. (Need to format the FW drives before I can store the folder there)
Any hints on breaking apart a large folder like that when storing onto DVD-RW or DVD-R.
Thanks for the suggestions,
Alex

It should be ok with -rw discs
things to look for are:
finger prints: whos got sticky fingers, ive been to customers houses and they've had jam on them then asked why they wont work
rough edges on disc or center hole, if this is rough its cant always seat properly and so may eject: i have got into the habit of sticking my finger in the center hole and spinning it round with my centre finger, also kinda relaxing too!
and obviously sctaches, like the jam stains! if its not a clear disk for any of these reasons it will spit it out, like a human eating mouldy food, the machines the same (but dont stick your pizza in there lol).
also make sure it hasnt been used before, if its been formatted in another machine, this can block it out.
if the worst is worst, get the laser cheked out, these things have 2, 1 for reading and 1 for burning so although it may read a disk it might not burn, and if the reader head has gone it wont do either becuase it needs to read it befor it can burn it.
good luck
al

Importing from one iPhoto library to another and retaining metadata.

I have an iPhoto 11 library stored on DVD. Each image in the Library has a number set as its title, 1 through to 350.
The actual names of the images in the filesystem have the format 'P1010004.jpg'.
I want to export the images from iPhoto so that they use the title for the filename so that they're numbered 1.jpg, 2.jpg etc (effectively renaming all the files to use the image title instead of the camera generated title). I know this possible using the File > Export dialog.
With the DVD inserted, the library appears in iPhoto in the 'Shared' section in the left-hand pane. I can navigate through the library on the DVD and the titles and metadata are appearing correctly when I click on 'info'
When I try to export directly from the DVD, the 'File > Export' option is disabled / greyed out. So I presume I need to import these images to my local library to allow me to then export them.
However, when I try and copy the images to my local library by dragging the images from Shared library to my local library (all within the iPhoto window), the image title data is lost, the title becomes the filename 'P1010004'.
I've tried copying the Image Library from the DVD to my local drive, then opening iPhoto with the 'alt' key to select this library, however iPhoto won't open it and the following error appears: You can’t open your current photo library using this version of iPhoto. However, I know that the DVD was created by iPhoto 11, the same version I'm using.
Can anyone please tell how I can import these images to my local library and retain the metadata.
Thanks,

I'm just wanting to export to a local folder.
I've looked at iPhoto Library Manager but it didn't seem to want to load Library I'm trying to merge, and I'm not convinced that iPLM is fully compatible with the latest version of iPhoto.
What I really don't understand is that iPhoto immediately recognises the library stored on the DVD, and it automatically pops up in the 'Shared' list on the left hand side.
However, if I first copy the Library from the DVD to my local drive, then try and open iPhoto with this library using the ALT key, I get the following error:
You can't open your current photo library using this version of iPhoto
You have made changes to your photo library using a newer version of iPhoto. Do you want to quit and use the latest version of iPhoto, or do you want to create a new photo library?
... which is strange because I'm using the latest version of iPhoto, and I know the iPhoto Library on the DVD was created using iPhoto 11.

How can i control what images load on my project to save preload time and avoid loading all images, elements, divs not yet visible?

Sup buddies,
How can I control what images load on my project to save preload time and avoid loading all images, elements, divs not yet visible?
As the project grows in size the load time increases. How does one control not loading all images ,divs,elements etc. until they're
needed on the timeline? For example some sections are off and only become visible when recalled. My projects slowly grow in size so loading
all images , is counter productive . My other option would be to create separate htmls but that breaks the seamless user experience .
TY...Over N Out...

hello, kiwi
quote: "Is there an easy way to burn a completed project to DVD, but keep only the (lo res, lo size) previews on my hard drive?"
yes.
maybe,...
1. you might think of making DVD backups first prior to importing the photos into Aperture. "Store Files: In their current location" once in Aperture make low rez Previews, and export finished Project.
or,
2. bring in the photographs to hard drive first prior to importing the photos into Aperture. "Store Files: In their current location" once in Aperture make low rez Previews, and export finished Project.
the low rez Previews will stay in Aperture but the high quality Versions will be exported onto DVDs and gone from the hard drive (if you delete the originals).
another way would be to export small about 50-70 pixel wide high quality jpegs to a folder on your Desktop and import & keep these in Aperture Library as a reference. make metadata to show where the original Project DVDs are stored and DVD filing system used.
victor

How do I transfer everything from my old iPod to the new one for FREE?

I just purchased a new iPod Classic (7th Gen) and need to copy everything over to my new iPod. I was trying to use "iPod 2 iPod" but they want $40 for it and I am not spending $40 just to do a one time transfer. Is there any program out there that dose what "iPod 2 iPod" dose but is FREE!!!!!!!!!!!!! and available for Windows?

NO, like most people I don't use iTunes like that, all my music is backed up on external hard drives and stored on DVD's, it is never all in the same place and I am not going to keep all my music on my computers hard drive and take up all the space. Now if only there was some magical amazing device that is like a laptop with a lot of storage space but only smaller that people could take anywhere to listen to all of there favorite music so they would not have to fill up there laptop or desktop's hard drive and/or drag around a computer where ever they go... oh wait, something like that already exists, it's called a #$%^*&! IPOD!!!. That is the whole point... The only place I keep most of my music on is my iPod but Apple and there infinite wisdom for some reason decided that iTunes would be the place where people would keep and manage their music and not the iPod, So since I can only sync my iPod with iTunes but CANT sync iTunes with my iPod I would be unable to do as you have suggested.
<Edited by Host>

***New*** iTunes 7 skipping songs problem (2-3 seconds of play only)

Hey all,
Long post here, but I hope you'll bear with me, as I reckon this is something of a new fault with iTunes 7.
Found a bug with iTunes 7 on my iPod Video which I don't see any references to from anyone else. (I presume I'm not alone, but I've Googled the **** out of this problem and no one else seems to specifically have it...)
Basically, with iTunes 6.0.5, all was well. For putting songs ONTO the iPod, I've been using Anapod Explorer for well over a year, again without any problems. (I don't usually keep much of a music library on the PC - it all gets stored on DVD-burned MP3 discs, so there is a backup, just not on the machine. For that reason, and for personal preferences with iTunes' own way of updating, I find Anapod's copy and paste approach to updating the iPod to be much handier.)
So, long story short, a few weeks ago I upgraded to iTunes 7. Left it a while longer than usual because I was burned by an earlier iPod software upgrade which stopped me from playing divx/xvid videos created using iPod Videora Converter - on that occassion, I had to pull the firmware BACK to what it was when I first got the iPod. Thankfully, whatever bug was in 1.1 in relation to home-created videos is no longer there, and 1.2 works perfectly well. The brightness feature is the main reason I risked changing the software again.
So you would have thought all would be well with the songs, then? Unfortunately not. iTunes 7, slick and all as it appears, seems to create a situation whereby, once I disconnect from iTunes, ALL songs suddenly only play for 1-3 seconds before STOPPING, with the 'playing' bar jumping all the way to the last second and holding there. Skip forward to the next song, and same thing!
This cannot be an issue in relation to Anapod, as it never affected iTunes seeing the songs updated to the iPod via that method before. What iTunes 7 does seem to have done, though, is prevent songs being played in the normal way by introducing this frustrating 'start, 3-seconds, stop' issue. It will eventually go to the next song after about 1-2 minutes of silence, and then the process repeats. Throughout all of this, the songs do play normally within iTunes 7(0.2) so it is not a hard drive or corrupt file problem.
I should say that this is not crucial or a desperate situation, as I've already found a way to fix it. Moving BACK to iTunes 6.0.5 (or any 6.x.x version) and playing a few songs within iTunes, and then disconnecting will miraculously return all the songs to the usual full playing ability.
Unfortunately for Apple, this means (for the second time in a year) that I cannot update to their latest release as it ruins the playability of my iPod. I would like the extra features in iTunes 7 (for playing songs on the computer - as I said I never used it for updating anyway), but this latest glitch means I'll be using the more stable and reliable 6 for some time to come.
What I'm curious from the good folks on the forums here is to see if any of you have heard of this exact problem until now, and if so, what solution anyone had to get around it (possibly including actually keeping iTunes 7!)
Thanks for the help. Sorry for the long post. It all seemed kind of necessary when I see so many posts about 'skipping songs' but never about 2-3 seconds worth of play (most usually say they get more than half way.)
iPod Video Windows XP

I've update the subject of your post to more accurately reflect the issue.

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.

Storing on DVD

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