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NTX vs. CDX

Posted: Wed Jul 14, 2010 2:59 pm
by melliott42
Hello,

I used Clipper back in the DOS days. I was happy with the .NTX index files. I heard for large indexes they became corrupt. Hopefully that has been fixed.

1. Is there any compelling reason to not use NTX indexes?
2. Would CDX put all the indexes in just one file (or one for each index as NTX does)?

Thanks,

Michael

Re: NTX vs. CDX

Posted: Wed Jul 14, 2010 4:18 pm
by esgici
Hello Michael
melliott42 wrote: I used Clipper back in the DOS days. I was happy with the .NTX index files.
Welcome our club :)
melliott42 wrote: I heard for large indexes they became corrupt. Hopefully that has been fixed.
Itsn't for only .NTXs, every index file (in fact every file) may corrupt.
melliott42 wrote: 1. Is there any compelling reason to not use NTX indexes?
Simply no. No drastic reason for not use nor use.
melliott42 wrote: 2. Would CDX put all the indexes in just one file (or one for each index as NTX does)?
It's correct. "C" in the beginning means "compound".

But only advantage isn't "all indexs is in single file" (beside putting all eggs in one basket), CDX indexs has more.

Moreover, if you use same name of .dbf as index file name (fe mytable.cdx for mytable.dbf) and set AUTOPEN on, the cdx file will open (set) with table automatically.

The price is, you have learn same extra concepts : bag, tag, order (slightly different than classical meaning) ...

Anyway, after learned, you don't will be repentant, I thing ;)

Regards

--

Esgici

Re: NTX vs. CDX

Posted: Wed Jul 14, 2010 11:36 pm
by cdsaenz
I agree that NTX ain't bad per se. I know serious applications with lot of data using big indexes. Reindexing from time to time is a good practice in those cases.

CDX is monolithic and should be faster/smaller. The bag stuff is nice and autoopen too.

Esgici, a question for you: how reliable is CDX implementation in Harbour? I ain't had the chance to really check that out. I believe it's production quality but just wanted to check out.

Thanks.

Re: NTX vs. CDX

Posted: Wed Jul 14, 2010 11:50 pm
by esgici
cdsaenz wrote: ...
how reliable is CDX implementation in Harbour? I ain't had the chance to really check that out. I believe it's production quality but just wanted to check out.
Hola Charly

Sadly I haven't any deeply experience, fe huge files, many tags and especially many years of usage, etc :(

But I always trust Harbour programmers; they are really very skilled persons. I havn't encountered any problem on implementation or performance problem against Clipper, especially database processing area.

Saludos

--

Esgici

Re: NTX vs. CDX

Posted: Thu Jul 15, 2010 12:44 am
by cdsaenz
Good feedback, thanks Esgici. Yes, I see the Harbour team has made a tremendous job for a loong time. It's time to develop! :)

Re: NTX vs. CDX

Posted: Thu Jul 15, 2010 9:46 am
by mustafa
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viewtopic.php?f=5&t=873
http://hmglights.wordpress.com/2010/03/ ... x-com-hmg/
viewtopic.php?f=5&t=1259
Saludos
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Re: NTX vs. CDX

Posted: Thu Jul 15, 2010 12:01 pm
by melliott42
Esgici,

Thanks for the info on CDX and NTX. That is very useful.

Michael