Re: Large Objects

Frank D. Engel, Jr. wrote:

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> I'd advise use of BYTEA as well. It's much simpler to work with than
> the OIDs, and has simpler semantics. You do need to escape data
> before handing it to the query string, and handle escaped results (see
> the docs), but overall much nicer than working with OIDs.

BYTEA is not always pragmatic. What is the file is 100 megs? 256 megs?

pg_largeobject is more efficient than BYTEA for larger binaries.

Sincerely,

Joshua D. Drake

>
> On Dec 31, 2004, at 1:21 AM, Bruno Wolff III wrote:
>
>> On Mon, Dec 27, 2004 at 10:39:48 -0600,
>> Dan Boitnott <dan(at)mcneese(dot)edu> wrote:
>>
>>> I need to do some investigation into the way Postgres handles large
>>> objects for a major project involving large objects. My questions are:
>>
>>
>> I don't know the answer to all of your questions.
>>
>>> * Is it practical/desirable to store files MIME-Encoded inside a
>>> text field?
>>
>>
>> This should be possible if the files aren't too large. bytea is
>> another type
>> that might be better to use.
>>
>>> * The obvious disadvantages:
>>> * slow, Slow, SLOW
>>
>>
>> If you always need to access the whole file this might not be too bad.
>> But if you only need to access a small part, you are going to pay a big
>> cost as the whole record will need to be retrieved before you can pick
>> out the part you want.
>>
>>> * significant increase in per-file storage requirements
>>
>>
>> It might not be too bad as large records can be compressed. That
>> should get
>> back some of the bloat from uuencoding.
>>
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> - -----------------------------------------------------------
> Frank D. Engel, Jr. <fde101(at)fjrhome(dot)net>
>
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