fix where clause when multiple features are filtered by ids (fixes #12616, followup d1e23a6)

(cherry picked from commit 02f5c73)

Author: jef-n

src/providers/oracle/qgsoracleprovider.cpp

@@ -461,7 +461,7 @@ QString QgsOracleUtils::whereClause( QgsFeatureIds featureIds, const QgsFields &
   {
     whereClauses << whereClause( featureId, fields, primaryKeyType, primaryKeyAttrs, sharedData );
   }
-  return whereClauses.join( " AND " );
+  return whereClauses.isEmpty() ? "" : whereClauses.join( " OR " ).prepend( "(" ).append( ")" );
 }
 
 

src/providers/postgres/qgspostgresprovider.cpp

@@ -545,7 +545,7 @@ QString QgsPostgresUtils::whereClause( QgsFeatureIds featureIds, const QgsFields
     whereClauses << whereClause( featureId, fields, conn, pkType, pkAttrs, sharedData );
   }
 
-  return whereClauses.join( " OR " );
+  return whereClauses.isEmpty() ? "" : whereClauses.join( " OR " ).prepend( "(" ).append( ")" );
 }
 
 QString QgsPostgresProvider::filterWhereClause() const

src/providers/spatialite/qgsspatialitefeatureiterator.cpp

@@ -44,6 +44,11 @@ QgsSpatiaLiteFeatureIterator::QgsSpatiaLiteFeatureIterator( QgsSpatiaLiteFeature
     whereClause += whereClauseFid();
   }
 
+  if ( request.filterType() == QgsFeatureRequest::FilterFids )
+  {
+    whereClause += whereClauseFids();
+  }
+
   if ( !mSource->mSubsetString.isEmpty() )
   {
     if ( !whereClause.isEmpty() )
@@ -196,6 +201,16 @@ QString QgsSpatiaLiteFeatureIterator::whereClauseFid()
   return QString( "%1=%2" ).arg( quotedPrimaryKey() ).arg( mRequest.filterFid() );
 }
 
+QString QgsSpatiaLiteFeatureIterator::whereClauseFids()
+{
+  QStringList whereClauses;
+  foreach ( const QgsFeatureId featureId, mRequest.filterFids() )
+  {
+    whereClauses << QString( "%1=%2" ).arg( quotedPrimaryKey() ).arg( featureId );
+  }
+  return whereClauses.isEmpty() ? "" : whereClauses.join( " OR " ).prepend( "(" ).append( ")" );
+}
+
 QString QgsSpatiaLiteFeatureIterator::whereClauseRect()
 {
   QgsRectangle rect = mRequest.filterRect();

src/providers/spatialite/qgsspatialitefeatureiterator.h

@@ -71,6 +71,7 @@ class QgsSpatiaLiteFeatureIterator : public QgsAbstractFeatureIteratorFromSource
 
     QString whereClauseRect();
     QString whereClauseFid();
+    QString whereClauseFids();
     QString mbr( const QgsRectangle& rect );
     bool prepareStatement( QString whereClause );
     QString quotedPrimaryKey();