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Memo bloat
Message
De
05/10/2005 08:12:54
 
 
À
05/10/2005 07:31:19
Information générale
Forum:
Visual FoxPro
Catégorie:
Base de données, Tables, Vues, Index et syntaxe SQL
Titre:
Versions des environnements
Visual FoxPro:
VFP 6 SP5
OS:
Windows XP
Network:
Windows 2000 Server
Database:
Visual FoxPro
Divers
Thread ID:
01056130
Message ID:
01056200
Vues:
24
>SNIP
>>>When a new memo is added or an existing is changed the blocks are allocated in 64 byte chuncks, so on average there is a waste of 32 bytes/memo
>>>Changing a memo does not happen 'in place', the whole memo is rewritten, the old apace is not re-used, hence the bloat
>>
>>This is not true, if LEN(memo) it doesn't overcome CEILING(LEN(memo)/BLOCKSIZE)*BLOCKSIZE
>>blocksize it rewritten the memo in place.
>>
>SNIP
>
>Fabio,
>
>Please check out Re: .FPT files - bloat and re-writing of file header Thread #971406 Message #972068
>
>It says, as I read it, that memo field is always re-written.
>
>cheers

hi Jim,

Funny. I had done a few tests after Fabio's reply and my tests indicated Fabio was right (he usually is). I created a free table and did 100,000 replaces.
But then, I had the table exclusively and not buffered

Thanks for digging this one up. I must have read that message before. Just could not remember it
Gregory
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