Motivations:
- consistency - we generally use expanded names, and this also
matches Qt API which uses Database instead of Db
- avoids unpredictable capitalization throughout API (mix of "Db"
and "DB")
Adds a new method to QgsVectorDataProvider to truncate the layer.
The base implementation requires DeleteFeatures capability and
is not optimised. Providers can return the FastTruncate capability
and override the base implementation with a provider specific
optimised version. This is done in this commit for the Postgres
and Spatialite providers.
a substring from a vector data provider
Base implementation iterates through all features, but
providers can override with optimised versions. Native
implementations for postgres, spatialite and OGR included.
default value SQL clauses
QgsVectorDataProvider now has two methods:
- defaultValueClause: returns SQL fragment which must be evaluated
by the provider to obtain the default value, eg sequence values
- defaultValue: returns the literal constant default value
for a field
Fixed the add relation functionnality: the table is sorted. When the code
was setting the sorted column, the row was sorted and the other columns it was
setting were set on the wrong row.
* Remove deprecated Qgis::WKBType and API cleanup
Renames QgsWKBTypes to QgsWkbTypes
Replaces usage of the enums:
* Qgis::WKBType with QgsWkbTypes::Type
* Qgis::GeometryType with QgsWkbTypes::GeometryType
Their values should be forward compatible (a fact that was already
explited up to now by casting between the types)
Renames some SSLxxx to SslXxx and URIxxx to UriXxx
* Fix build warnings and simplify type handling
* Add a fixer to rewrite imports
* The forgotten rebase conflictThe forgotten rebase conflicts
* QgsDataSourcURI > QgsDataSourceUri
* QgsWKBTypes > QgsWkbTypes
* Qgis.WKBGeom > QgsWkbTypes.Geom
* Further python fixes
* Guess what... Qgis::wkbDimensions != QgsWkbTypes::wkbDimensions
* Fix tests
* Python 3 updates
* [travis] pull request caching cannot be disabled
so at least use it in r/w mode
* Fix python3 print in plugins
All pointer based methods have been removed.
Now we have only:
void setGeometry( const QgsGeometry& geom )
and
QgsGeometry geometry() const
Benefits include avoiding a whole lot of tricky pointer lifetime
issues, potential memory leaks, and finally closing #777, which
has survived for over 9 years!...
Impacts on PyQGIS code:
- no more need for the messy
g = QgsGeometry( feature.geometry() )
workaround, just use g = feature.geometry() instead
- IMPORTANT: you can no longer test whether a feature has geometry
using `if f.geometry():`, since QgsFeature::geometry() will
*always* return an object. Instead, use
`if not f.geometry().isEmpty():`, or preferably the new method
`if not f.hasGeometry():`
Fix#777
This commit adds a number of different forms of aggregates to
the expression engine.
1. Aggregates within the current layer, eg sum("passengers")
Supports sub expressions (ie sum("passengers"/2) ), group by
( sum("passengers", group_by:="line_segment") ), and optional
filters ( sum("passengers", filter:= "station_class" > 3 ) )
2. Relational aggregates, which calculate an aggregate over
all matching child features from a relation, eg
relation_aggregate( 'my_relation', 'mean', "some_child_field" )
3. A summary aggregate function, for calculating aggregates
on other layers. Eg aggregate('rail_station_layer','sum',"passengers")
The summary aggregate function supports an optional filter,
making it possible to calculate things like:
aggregate('rail_stations','sum',"passengers",
intersects(@atlas_geometry, $geometry ) )
for calculating the total number of passengers for the stations
inside the current atlas feature
In all cases the calculations are cached inside the expression
context, so they only need to be calculated once for each
set of expression evaluations.
Sponsored by Kanton of Zug, Switzerland
