Extent
EXTENT(n Geometry)
Alias: ST_EXTENT
Returns a bounding rectangle around all the geometries in n.
Result type: point or polygon
Examples:
SELECT ASTEXT(EXTENT(shape)) AS mbr FROM sometable;
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mbr
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POLYGON((13.08 52.34, 13.08 52.68, 13.75 52.68, 13.75 52.34, 13.08 52.34))
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SELECT type, ASTEXT(EXTENT(shape) AS mbr FROM sometable GROUP BY type;
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type | mbr
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school | POLYGON((13.12 52.39, 13.12 52.64, 13.70 52.64, 13.70 52.39, 13.12 52.39))
hospital | POLYGON ((13.14 52.38, 13.14 52.64, 13.57 52.64, 13.57 52.38, 13.14 52.38))
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