Re: [SQL] EXTERNAL storage and substring on long strings

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От Jan Wieck
Тема Re: [SQL] EXTERNAL storage and substring on long strings
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Msg-id 3F3BDB2A.40506@Yahoo.com
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Ответ на Re: [SQL] EXTERNAL storage and substring on long strings  (Tom Lane <tgl@sss.pgh.pa.us>)
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Tom Lane wrote:

> Jan Wieck <JanWieck@Yahoo.com> writes:
>> Doesn't look that unrealistic to me. A plain text based substring
>> function will reassemble the whole beast first before cutting out the
>> wanted part. His manually chunked version will read only those chunks
>> needed.
>
> So does substr(), if applied to EXTERNAL (non-compressed) toasted text.
> See John Gray's improvements a release or two back.

Duh ... of course, EXTERNAL is uncompressed ... where do I have my head?


Jan

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