Thunderbird 3 is a pain in the neck

[Amedee Van Gasse (u2s)]

On Mon, March 1, 2010 08:53, Christopher Chan wrote:

> Nevermind, it was the daft synchronize all files default. I/O went
> through the roof.

Yeah, I/O can be a female dog. :)

>>>>> Outlook Express with its foxpro database is probably the fastest for
>>>>> this sort of thing.
>>>>
>>>> Foxpro? Really? Do you have any sources about that? I can't find
>>>> anything on Google that confirms it.
>>>
>>> Nope. Just hearsay. Those cannot possibly be dbase files could they?
>>>
>>>
>>>>
>>>> It's not that I don't believe you, but at a previous job our main
>>>> product was built with FoxPro, so I'm a bit familiar with that
>>>> database
>>>> format, but I never noticed that OE uses it.
>>>
>>> Well, it uses some form of database. Foxpro is listed for the file
>>> extension of the 'Outlook Express format' file dbx.
>>> http://filext.com/file-extension/DBX
>>
>> That website is not reliable. The file extension doesn't tell you
>> everything, you should look at the file header: the first few bytes of a
>> file. The Linux utility 'file' uses that approach to determine a file
>> type. But you could see it yourself when you open an OE dbx file with a
>> hex editor and compare that with a real foxpro file.
>
> Yes, I have not bothered checking yet because it was a programmer that
> told me about it. I'll look after I get quicktime deployed across all
> the school computers.

Ahhh yes programmers...
Never trust a programmer who claims something about software that he
hasn't written himself, and that he can't back with hard evidence. And
don't trust him with a screwdriver either. ;-)

>> It doesn't make sense to store email in a database format, because
>> databases have fixed-width fields and email is variable-width.
>>
>
> You have heard about this thing called Exchange right?

You may guess 3 times what my day job is. Or better yet, google for my
full name and add 'exchange' to the query.

> I am not saying
> that this means Outlook Express is using foxpro (or some other database
> format) for its mailboxes but such, er, weird things do exist. Databases
> have also moved beyond fixed-width fields too but not sure what foxpro
> supports...

When you're talking about Foxpro, you're talking about old skool
dbase-type databases, where 1 table == 1 file. There is no layer of
abstraction between the database engine and the filesystem. That's what I
meant. Foxpro supports variable-width fields called memo fields. These are
used to store binary blobs of data. But they are not optimized for
performance.
Records are read sequentially, unless there is an index (some kind of
binary tree) to speed up queries. MySQL is actually quite similar to old
skool dBase from that point of view.

The new generation of databases doesn't use the file=table paradigm. In
that sense the OE message store as well as the exchange messages store
(mdb) are also databases, but they add another abstraction layer between
the database engine and the file system. SQL server is similar. The data
isn't physically stored in tables, but in some kind of binary tree.

Sorry, I don't want to give you a lecture on databases.