Cluster index?

Hi there, I have a question about clustered index Please see if you can help. If Informix doesn't support clustered index than please ignore all of the below: Is cluster index only available on certain version or any version of Informix? Does the primary key have a clustered index by defaut? Can I have more than one clustered indexes in a table? Thanks in advance for you help. Tung Nguyen

On Wed, 22 Mar 2000 05:22:33 GMT, "Nguyen Thanh" <vanthanh@home.com> wrote: 1. YES 2. NO 3, NO >Hi there, > >I have a question about clustered index Please see if you can help. >If Informix doesn't support clustered index than please ignore all of the >below: > > Is cluster index only available on certain version or any version of >Informix? >Does the primary key have a clustered index by defaut? >Can I have more than one clustered indexes in a table? > >Thanks in advance for you help. > >Tung Nguyen >

the clustered index is in most flavors of Informix. You do not get a clustered key by default. You can only have one clustered key per table. Nona >Subject: Cluster index? >From: "Nguyen Thanh" vanthanh@home.com >Date: 22.03.00 06:22 W. Europe Standard Time >Message-id: <tMYB4.56108$Hq3.1296662@news2.rdc1.on.home.com> > >Hi there, > >I have a question about clustered index Please see if you can help. >If Informix doesn't support clustered index than please ignore all of the >below: > > Is cluster index only available on certain version or any version of >Informix? >Does the primary key have a clustered index by defaut? >Can I have more than one clustered indexes in a table? > >Thanks in advance for you help. > >Tung Nguyen > > > > > > > >

I am a novice with informix programming and have downloaded the trial linux version . Where can i get instuctions to install it. I don't have a clue. Please help Thanks

Why would you want to use Informix voluntarily? I am cursing every time I am bothered with it! And it seems to be really difficult to get help with problems (even though my company is paying for support!) Get Oracle, it will save you lots of trouble! Simone MR B SINGH wrote in message <954084096.28612.0.nnrp-01.c2def583@news.demon.co.uk>... :I am a novice with informix programming and have downloaded the trial :linux version . :Where can i get instuctions to install it. :I don't have a clue. :Please help :Thanks : :

"MR B SINGH" <bal@u-comms.demon.co.uk> writes: > I am a novice with informix programming and have downloaded the trial > linux version . > Where can i get instuctions to install it. > I don't have a clue. > Please help > Thanks I guess the online documentation is a good starting point: http://www.informix.com/documentation/ To me "Installation Resource" sounds right... http://www.informix.com/informix/resource/ Thomas (If you don't have a clue, get a clue;)

Nguyen Thanh wrote: > > Hi there, > > I have a question about clustered index Please see if you can help. > If Informix doesn't support clustered index than please ignore all of the > below: > > Is cluster index only available on certain version or any version of > Informix? > Does the primary key have a clustered index by defaut? > Can I have more than one clustered indexes in a table? Sujit and Obnoxio gave complete answers to the question as asked, however, I would like to address an unasked question that seems to be there. If you are coming from a Sybase background you should know that Informix's idea of a CLUSTERED index and Sybase's idea of a CLUSTER index are VERY DIFFERENT. Sybase CLUSTER indexes move the table's rows into the index removing the 'normal' data pages and attach the rows to the index nodes directly. These indexes are automatically maintained in order even as the table grows and is modified and are VERY efficient for single row queries and DISMAL for sequential scans of this table ORDERed BY ANY key henceforth! Informix's CLUSTERED index simply sorts the table so that immediately following the index creation (or reorganization with ALTER INDEX TO CLUSTER) each row is contiguous with the rows withimmediately higher and lower key values and an index on that key has been created. This index is EXACTLY as efficient as any other index at locating a single row BUT VERY EFFICIENT for sequential scans of the table ORDERed BY that index's key. The clustered nature of the data is NOT maintained over time, new rows are appended to the end or fill in deleted row spaces, and the index must be reclustered periodically to maintain the performance advantage this feature provides. So Sybase's CLUSTER indexes improve small keyed queries while Informix's CLUSTERED indexes improve large sequential queries. -- Art S. Kagel & Family kagel@erols.com

Simone Jesse wrote: > Why would you want to use Informix voluntarily? > I am cursing every time I am bothered with it! > And it seems to be really difficult to get help with problems (even though > my company is paying for support!) > Get Oracle, it will save you lots of trouble! > Simone, I do not understand your troubles. In over 17 years using Informix products I have always found their tech support to be superior to most others in the industry (OK there was that two year period just before Jim H. took over support operations but it was ten years ago and I'll put that asside). Oracle's support on the other hand always keeps me on hold for minutes at a time, the engineers NEVER have an immediate answer and when they call back they fax me a position paper or HOW-TO equivalent that someone prepared two years before. Yes it is nice that they have those available but I want someone to talk to me about my problem, tell me why it is or is not a problem, how it happened, when it will be fixed (if a software bug), how to work around it until then, and talk me through at least the beginnings of it. And I'm no novice at this, I cannot imagine how a new user/administrator gets anything useful from Oracle support. Art S. Kagel > Simone > > MR B SINGH wrote in message > <954084096.28612.0.nnrp-01.c2def583@news.demon.co.uk>... > :I am a novice with informix programming and have downloaded the trial > :linux version . > :Where can i get instuctions to install it. > :I don't have a clue. > :Please help > :Thanks > : > :

PC User wrote: > > > Simone, I do not understand your troubles. In over 17 years using Informix > products I have always found their tech support to be superior to most others > in the > industry I must admit I agree with this... Take, for instance, two examples I've had dealing with two of my consulting clients and their respective DBMSs: (1) A High Performance environment using Oracle. (last year) First of all, the Oracle tech was unable to install Oracle 7 on a Unix system. I had to be called in to show him how to set environment variables. He then followed the instructions straight from the book, charging about three times what I did for a job I was equally competent to do. When Oracle decided to misbehave and take complete, 100% control of one of the system CPUs (losing us a large number of critical, expensive CPU cycles) they were completely unable to help and it took us a couple of weeks to get our CPU back. (2) An ageing, but mission critical business system using Informix. (current) I'm currently experiencing a problem with making connections to an old(!) Informix database (Informix SE 5.10) at a client's site using ESQL/C. When I call Informix, their guy is friendly and knowledgeable. He's helped me avoid damaging the system (which I, in my relatively ignorant-of-Informix state might have done) and gone, IMO, well beyond the call of duty in providing help. Although the problem isn't yet resolved (it's a particularly bizarre and perverse one), the next step is that he's offered to dial into the client's box to have a direct look at the problem himself. What's more, while I really think Informix is overpriced (SE, at least, gives me no more significant functionality than the cheaper Interbase), Oracle's pricing is simply ridiculous. (Bear in mind this perspective is from a country with a really weak currency -- ZAR6.5 = US$1 today. ) *shrug* -- I'm still thinking of using Oracle on a new commercial project, but will avoid it if I can replace the planned development tool with something supporting a wider array of DBMSs. Oh well, chacun a son gout... Hal