I've actually been running it with synchronous=off. Unfortunately, it  
doesn't seem to run any faster and still creates a journal file.

_Nik

On Mar 17, 2009, at 6:05 PM, Jim Wilcoxson wrote:

> Drop is executed within a transaction, which means that every record
> you touch has to be backed up to the journal first, then modified in
> the database.  I'm guessing that if you use pragma synchronous=off, it
> would speed up the drop index, but you'd take a chance on corrupting
> the database if the machine crashed during the drop.
>
> It would probably be faster to make a copy of the database (all
> sequential I/O), then drop the index with synchronous=off in one of
> the copies (no journal I/O), then use vacuum if you want to really
> clean up the DB.  If something goes wrong, you still have your backup
> copy.
>
> I haven't actually tried this; let us know if it makes a big  
> difference.
>
> Jim
>
> On 3/17/09, Nikolas Stevenson-Molnar <steve...@evergreen.edu> wrote:
>> Hi,
>>
>> I'm trying to drop an index on a table with about 8 million rows and
>> it's taking a very long time. I can understand why building the index
>> would take some time, but why dropping it? And is there any way to
>> speed it up?
>>
>> Thanks!
>> _Nik
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>
>
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