Re: Large Objects

On Jan 1, 2005, at 11:40 AM, Joshua D. Drake wrote:

>
>>>
>> Intresting.
>> What is the size when bytea become inafective ?
>>
>> Currently i keep all my products images in bytea record. is it
>> practical ?
>
> Well I am going to make the assumption that you product images are
> small...
> sub 100k or something. Bytea is just fine for that. The problem is when
> the binary you want to store is 50 megs. When you access that file you
> will be using 50 megs of ram to do so.
>
> Large Objects don't work that way, you don't have the memory overhead.
> So
> it really depends on what you want to store.
>

I prefer the _idea_ of using large objects but am worried about the
implications.  Without them I can back up the database using pg_dump
and get a single tar file which can perfectly represent the database.
This gives me (and those on high) the warm-fuzzies.  If I store files
(PDFs of varying sizes by the way, say from 500k to 50M) as large
objects, will I still be able to restore the _whole_ database from a
single pg_dump tar file?

>
>>
>> how slower is it then accessing an image on a file system ( like ext3
>> ) ?
>
> Well that would be an interesting test. Ext3 is very slow. I would
> assume
> that Ext3 would be faster just because of the database overhead.
> However you gain from having the images in the database for
> flexibility and manageability.
>
> Sincerely,
>
> Joshua D. Drake
>
>
>
>>
>>
>> Cheers
>>
>>>
>>> pg_largeobject is more efficient than BYTEA for larger binaries.
>>>
>>> Sincerely,
>>>
>>> Joshua D. Drake
>>>
>>>
>>
>
>
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