Re: [HACKERS] pg_dump/restore to convert BLOBs to LZTEXT (optional!) - Mailing list pgsql-general

From Philip Warner
Subject Re: [HACKERS] pg_dump/restore to convert BLOBs to LZTEXT (optional!)
Date
Msg-id 3.0.5.32.20000804112928.026df4f0@mail.rhyme.com.au
Whole thread Raw
In response to Re: [HACKERS] pg_dump/restore to convert BLOBs to LZTEXT (optional!)  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-general
At 21:10 3/08/00 -0400, Tom Lane wrote:
>As well as break the semantics: if you have a multiply-referenced BLOB
>then you can update it through any reference and the changes are visible
>through all the references.  Not so after you convert the data into
>non-BLOB values.

That's what I meant. People *shouldn't* expect BLOB fields to be updated in
more than one table, but the implementation currently allow it (since BLOBs
are not implemented as fields).


>I don't see that pg_dump can help meaningfully,
>and I'd just as soon resist feature bloat in pg_dump.

Fine. Thinking about it, even *if* it was implemented as a utility, I
suspect (for the reasons you outlined), conversion would be a multi-step
process. And a more useful utility would be one that converted an existing
database, rather than trying to everything in the 'restore'...

Forget I even mentioned it.


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