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Re: Difference between Well-Known Binary data format and MySql blob format
Posted by: Alexey Botchkov
Date: August 02, 2005 01:24AM

Presently, content of the GEOMETRY field is basically WKB with the SRID.
But I wouldn't recommend to rely on that - we have plans to change that.
If you need to get proper WKB of the object, you should use AsWKB function:
SELECT AsWKB(geom_field) FROM geom_table;

Here is the description of the WKB of the POINT from OpenGIS info:
WKBPoint {
byte byteOrder;
uint32 wkbType;
Point point; /* actually two doubles */
}

So it makes 1 + 4 + 8 + 8 = 21 bytes

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Re: Difference between Well-Known Binary data format and MySql blob format
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