This provider option was linked to the project level option
"Trust layer metadata..." which was implemented
to speed up loading of large dataset by trusting extent
read from metadata to avoid costly operations to determine
the layer extent.
Check PK unicity on the other hand has only effect on views
and query layers and it is useful as an independent
option to prevent loading of layers that have no PK (or the
wrong one).
But the operation of determine unicity of a values in a column
can also be costly, so better to get control back to the user.
Legacy default is preserved (the project-level "Trust..." option).
Fixes#21839
Funded by RAAB.nl
for QgsVectorLayer, when constructing a layer with a URI which
may be invalid
These may be used for layers where the geometry type/CRS is
known in advance, and where the layer path may not be
initially resolvable. (E.g. layers with a URI pointing to a
non-existant file). It is only ever used if the layer cannot
be resolved, otherwise the actual layer geometry type will be
detected and used for the layer.
... you are too slow and QJson API is so ugly.
Now using this wonderful json lib:
https://github.com/nlohmann/json
Results in release mode (QJson tests are not shown but
QJson was even slower than string concat).
PASS : TestQgsJsonUtils::testExportAttributesJson(Use json)
RESULT : TestQgsJsonUtils::testExportAttributesJson():"Use json":
0.0022 msecs per iteration (total: 75, iterations: 32768)
PASS : TestQgsJsonUtils::testExportAttributesJson(Use old string concat)
RESULT : TestQgsJsonUtils::testExportAttributesJson():"Use old string concat":
0.0032 msecs per iteration (total: 54, iterations: 16384)
PASS : TestQgsJsonUtils::testExportFeatureJson(Use json)
RESULT : TestQgsJsonUtils::testExportFeatureJson():"Use json":
0.011 msecs per iteration (total: 96, iterations: 8192)
PASS : TestQgsJsonUtils::testExportFeatureJson(Use old string concat)
RESULT : TestQgsJsonUtils::testExportFeatureJson():"Use old string concat":
0.015 msecs per iteration (total: 64, iterations: 4096)
PASS : TestQgsJsonUtils::testExportGeomToJson(Use json)
RESULT : TestQgsJsonUtils::testExportGeomToJson():"Use json":
0.76 msecs per iteration (total: 98, iterations: 128)
PASS : TestQgsJsonUtils::testExportGeomToJson(Use old string concat)
RESULT : TestQgsJsonUtils::testExportGeomToJson():"Use old string concat":
0.85 msecs per iteration (total: 55, iterations: 64)
PASS : TestQgsJsonUtils::cleanupTestCase()
We can use this when restoring the layer, if the uri turns out
to be invalid at that stage (e.g. a file has moved). By storing
and falling back to the last known wkb type, we avoid unnecessarily
discarding the existing layer renderer, and can still show the
expected layer type in the layer tree.
... and add a getter for coordinateTransform to QgsMapLayer
The reason is that I think we should reduce the dataProvider API
usage and rely on the higher level QgsMapLayer API whenever it
is possible, QgsMapLayer checks for data provider validity
and returns a default constructed QgsCoordinateTransform instead
of crashing.
