GeometryN
GEOMETRYN(g Geometrycollection, n interger)
Alias: ST_GEOMETRYN
Returns the nth object from g.
Result type: geometry
Example:
SELECT ASTEXT(GEOMETRYN(MLINEFROMTEXT('MULTILINESTRING((1 1, 9 1), (2 2, 8 2))'), 2));
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col1
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LINESTRING (2 2, 8 2)
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