[OGR provider] Optimize feature requests with OrderBy clauses on a GeoPackage dataset #53266
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Just move existing code from QgsOgrProviderUtils::setSubsetString() to it
…oPackage dataset (fixes qgis#53198) OrderBy clauses are translated into a "SELECT ... FROM ... [WHERE ...] ORDER BY ... [LIMIT x]" SQL statement evaluated by GDAL On a 3.2 million feature GeoPackage, this decreases the RAM consumption from 6 GB to 0.5 GB, and is 50% faster. If a limit clause is added with a small number, then the speed-up is massive.
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nyalldawson
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Jun 9, 2023
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(fixes #53198)
OrderBy clauses are translated into a
"SELECT ... FROM ... [WHERE ...] ORDER BY ... [LIMIT x]" SQL statement
evaluated by GDAL
On a 3.2 million feature GeoPackage, this decreases the RAM consumption
from 6 GB to 0.5 GB, and is 50% faster. If a limit clause is added with
a small number, then the speed-up is massive.