Don't send expressions with special fields to provider

qgis · Aug 14, 2015 · 480a0f1 · 480a0f1
1 parent fee5da9
commit 480a0f1
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Showing 3 changed files with 35 additions and 0 deletions.
diff --git a/python/core/qgsfeaturerequest.sip b/python/core/qgsfeaturerequest.sip
@@ -54,6 +54,16 @@ class QgsFeatureRequest
     QgsFeatureRequest& setFilterExpression( const QString& expression );
     QgsExpression* filterExpression() const;
 
+    /**
+     * Disables filter conditions.
+     * The spatial filter (filterRect) will be kept in place.
+     *
+     * @return The object the method is called on for chaining
+     *
+     * @note Added in 2.12
+     */
+    QgsFeatureRequest& disableFilter();
+
     //! Set flags that affect how features will be fetched
     QgsFeatureRequest& setFlags( Flags flags );
     const Flags& flags() const;

diff --git a/src/core/qgsfeaturerequest.h b/src/core/qgsfeaturerequest.h
@@ -112,6 +112,16 @@ class CORE_EXPORT QgsFeatureRequest
     QgsFeatureRequest& setFilterExpression( const QString& expression );
     QgsExpression* filterExpression() const { return mFilterExpression; }
 
+    /**
+     * Disables filter conditions.
+     * The spatial filter (filterRect) will be kept in place.
+     *
+     * @return The object the method is called on for chaining
+     *
+     * @note Added in 2.12
+     */
+    QgsFeatureRequest& disableFilter() { mFilter = FilterNone; return *this; }
+
     //! Set flags that affect how features will be fetched
     QgsFeatureRequest& setFlags( Flags flags );
     const Flags& flags() const { return mFlags; }

diff --git a/src/core/qgsvectorlayerfeatureiterator.cpp b/src/core/qgsvectorlayerfeatureiterator.cpp
@@ -117,6 +117,21 @@ QgsVectorLayerFeatureIterator::QgsVectorLayerFeatureIterator( QgsVectorLayerFeat
     mProviderRequest.setSubsetOfAttributes( providerSubset );
   }
 
+  if ( mProviderRequest.filterType() == QgsFeatureRequest::FilterExpression )
+  {
+    Q_FOREACH( const QString& field, mProviderRequest.filterExpression()->referencedColumns() )
+    {
+      int idx = source->mFields.fieldNameIndex( field );
+
+      // If there are fields in the expression which are not of origin provider, the provider will not be able to filter based on them.
+      // In this case we disable the expression filter.
+      if ( source->mFields.fieldOrigin( idx ) != QgsFields::OriginProvider )
+      {
+        mProviderRequest.disableFilter();
+      }
+    }
+  }
+
   if ( mSource->mHasEditBuffer )
   {
     mChangedFeaturesRequest = mProviderRequest;