TIP, how to fight with corrupted indexing

[Ruslan Zasukhin]

on 2/1/03 3:11 AM, Keith DeLong at delong at redcort.com wrote:

>> Woah... is this (corrupted indexing) a common situation?  I'm
>> developing right now for a product that will (hopefully) be in the
>> hands of hundreds of students within 6 months, and I can't have the
>> database not performing searches properly, due to indexing problems.
>> Because of the wide distribution, I wanted everything in one file, but
>> if this is a serious problem, I'll do it in multiple files.  For the
>> next year or so, users should only have one database; down the line
> 
> I've never seen an index corruption in normal program operation. In the case
> of a system/application crash, indexes get hammered with some frequency.
> 
> So if your target audience locks up computers, crashes apps, and otherwise
> misbehaves (read: STUDENTS), add a Rebuild Indexes menu item or better yet
> automatically rebuild your db indexes at each program launch. The rebuild is
> a 2-3 second process with my 10MB database files. YMMV.

Hi All,

Yes, described problem with index MAY come after outside failure during
ADD/UPDATE operation.

Valentina now has 2 mechanism to fight with this
    -- flag GoodClose
    -- index has in the header the number of records

On open Valentina try define if db was not closed correctly,
If yes, then Valentina start to check if index has the same number of
records as table. If no, then index is rebuilt.

Aha, I see weak side here.

In case of Update, wrong index will not be recognized.
It needs simply store in index TimeStamp of last change.
Okay I will do this in 2.0

For now you can try reduce risk of this, ifyou self add in your prefs
The flag "DbClosed". So on next open you can REINDEX db if it is FALSE.

-- 
Best regards,
Ruslan Zasukhin      [ I feel the need...the need for speed ]
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e-mail: ruslan at paradigmasoft.com
web: http://www.paradigmasoft.com

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