[postgis-devel] dumper and WKB

strk strk at keybit.net
Wed Nov 26 08:02:31 PST 2003


I've committed latest changes to dumper.

<ReportStart>

WKB parsing is disabled by default, to enable
it set USE_WKB define to 1 (or whatever else).

*SPEED ISSUE*

Slowness is mainly due to conversions, currently:
GEOMETRY->binWKB->hexWKB->bytea->binWKB

I've tried making my own HexDecoder to reduce this to:
GEOMETRY->binWKB->hexWKB->binWKB
but it is failing...

Best would be to avoid hex encoding as in:
GEOMETRY->binWKB
And this was the initial idea.

Anyway, this would require a double table scan since a BINARY cursor
would not be adeguate for other data types (for endiannes issues).
I will implement this, but WKB parsing will not change, so if you can
give it a try now your tests will not be a waste of time.

*CORRECTNESS ISSUE*

As far as I can tell it is working, so we should not have dataloss
now. Can you test it ?

*NULL HANDLING*

There is currently no NULL handling. I have a question here:
Are EMPTY geometries encoded in WKB, and how ?

</ReportEnd>

Thanks for your attention

--strk;



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