diff --git a/src/providers/ogr/qgsogrprovider.cpp b/src/providers/ogr/qgsogrprovider.cpp
index 17b82281a64..5edbc50ba23 100644
--- a/src/providers/ogr/qgsogrprovider.cpp
+++ b/src/providers/ogr/qgsogrprovider.cpp
@@ -246,7 +246,7 @@ bool QgsOgrProvider::setSubsetString( QString theSQL, bool updateFeatureCount )
                   .arg( quotedIdentifier( OGR_FD_GetName( OGR_L_GetLayerDefn( ogrOrigLayer ) ) ) )
                   .arg( mSubsetString );
     QgsDebugMsg( QString( "SQL: %1" ).arg( sql ) );
-    ogrLayer = OGR_DS_ExecuteSQL( ogrDataSource, mEncoding->fromUnicode( sql ).constData(), NULL, NULL );
+    ogrLayer = OGR_DS_ExecuteSQL( ogrDataSource, TO8( sql ), NULL, NULL );
 
     if ( !ogrLayer )
     {
@@ -921,7 +921,7 @@ bool QgsOgrProvider::addAttributes( const QList<QgsField> &attributes )
         continue;
     }
 
-    OGRFieldDefnH fielddefn = OGR_Fld_Create( mEncoding->fromUnicode( iter->name() ).data(), type );
+    OGRFieldDefnH fielddefn = OGR_Fld_Create( TO8( iter->name() ), type );
     OGR_Fld_SetWidth( fielddefn, iter->length() );
     OGR_Fld_SetPrecision( fielddefn, iter->precision() );
 
@@ -1074,7 +1074,7 @@ bool QgsOgrProvider::createSpatialIndex()
 
   QString sql = QString( "CREATE SPATIAL INDEX ON %1" ).arg( quotedIdentifier( layerName ) );  // quote the layer name so spaces are handled
   QgsDebugMsg( QString( "SQL: %1" ).arg( sql ) );
-  OGR_DS_ExecuteSQL( ogrDataSource, mEncoding->fromUnicode( sql ).data(), OGR_L_GetSpatialFilter( ogrOrigLayer ), "" );
+  OGR_DS_ExecuteSQL( ogrDataSource, TO8( sql ), OGR_L_GetSpatialFilter( ogrOrigLayer ), "" );
 
   QFileInfo fi( mFilePath );     // to get the base name
   //find out, if the .qix file is there
@@ -1087,8 +1087,8 @@ bool QgsOgrProvider::createAttributeIndex( int field )
   QString layerName = OGR_FD_GetName( OGR_L_GetLayerDefn( ogrOrigLayer ) );
   QString dropSql = QString( "DROP INDEX ON %1" ).arg( quotedIdentifier( layerName ) );
   QString createSql = QString( "CREATE INDEX ON %1 USING %2" ).arg( quotedIdentifier( layerName ) ).arg( fields()[field].name() );
-  OGR_DS_ExecuteSQL( ogrDataSource, mEncoding->fromUnicode( dropSql ).data(), OGR_L_GetSpatialFilter( ogrOrigLayer ), "SQL" );
-  OGR_DS_ExecuteSQL( ogrDataSource, mEncoding->fromUnicode( createSql ).data(), OGR_L_GetSpatialFilter( ogrOrigLayer ), "SQL" );
+  OGR_DS_ExecuteSQL( ogrDataSource, TO8( dropSql ), OGR_L_GetSpatialFilter( ogrOrigLayer ), "SQL" );
+  OGR_DS_ExecuteSQL( ogrDataSource, TO8( createSql ), OGR_L_GetSpatialFilter( ogrOrigLayer ), "SQL" );
 
   QFileInfo fi( mFilePath );     // to get the base name
   //find out, if the .idm file is there
@@ -1118,7 +1118,7 @@ bool QgsOgrProvider::deleteFeatures( const QgsFeatureIds & id )
 
   QString sql = QString( "REPACK %1" ).arg( layerName );   // don't quote the layer name as it works with spaces in the name and won't work if the name is quoted
   QgsDebugMsg( QString( "SQL: %1" ).arg( sql ) );
-  OGR_DS_ExecuteSQL( ogrDataSource, mEncoding->fromUnicode( sql ).data(), NULL, NULL );
+  OGR_DS_ExecuteSQL( ogrDataSource, TO8( sql ), NULL, NULL );
 
   recalculateFeatureCount();
 
@@ -1747,7 +1747,7 @@ QGISEXTERN bool createEmptyDataSource( const QString &uri,
       if ( precision < 0 )
         precision = 3;
 
-      field = OGR_Fld_Create( codec->fromUnicode( it->first ).data(), OFTReal );
+      field = OGR_Fld_Create( TO8( it->first ), OFTReal );
       OGR_Fld_SetWidth( field, width );
       OGR_Fld_SetPrecision( field, precision );
     }
@@ -1756,7 +1756,7 @@ QGISEXTERN bool createEmptyDataSource( const QString &uri,
       if ( width < 0 || width > 10 )
         width = 10;
 
-      field = OGR_Fld_Create( codec->fromUnicode( it->first ).data(), OFTInteger );
+      field = OGR_Fld_Create( TO8( it->first ), OFTInteger );
       // limit to 10.  otherwise OGR sets it to 11 and recognizes as OFTDouble later
       OGR_Fld_SetWidth( field, width );
     }
@@ -1765,7 +1765,7 @@ QGISEXTERN bool createEmptyDataSource( const QString &uri,
       if ( width < 0 || width > 255 )
         width = 255;
 
-      field = OGR_Fld_Create( codec->fromUnicode( it->first ).data(), OFTString );
+      field = OGR_Fld_Create( TO8( it->first ), OFTString );
       OGR_Fld_SetWidth( field, width );
     }
     else
@@ -1880,10 +1880,10 @@ void QgsOgrProvider::uniqueValues( int index, QList<QVariant> &uniqueValues, int
     sql += QString( " WHERE %1" ).arg( mSubsetString );
   }
 
-  sql += QString( " ORDER BY %1" ).arg( fld.name() );
+  sql += QString( " ORDER BY %1" ).arg( quotedIdentifier( fld.name() ) );
 
   QgsDebugMsg( QString( "SQL: %1" ).arg( sql ) );
-  OGRLayerH l = OGR_DS_ExecuteSQL( ogrDataSource, mEncoding->fromUnicode( sql ).data(), NULL, "SQL" );
+  OGRLayerH l = OGR_DS_ExecuteSQL( ogrDataSource, TO8( sql ), NULL, "SQL" );
   if ( l == 0 )
     return QgsVectorDataProvider::uniqueValues( index, uniqueValues, limit );
 
@@ -1914,7 +1914,7 @@ QVariant QgsOgrProvider::minimumValue( int index )
     sql += QString( " WHERE %1" ).arg( mSubsetString );
   }
 
-  OGRLayerH l = OGR_DS_ExecuteSQL( ogrDataSource, mEncoding->fromUnicode( sql ).data(), NULL, "SQL" );
+  OGRLayerH l = OGR_DS_ExecuteSQL( ogrDataSource, TO8( sql ), NULL, "SQL" );
 
   if ( l == 0 )
     return QgsVectorDataProvider::minimumValue( index );
@@ -1948,7 +1948,7 @@ QVariant QgsOgrProvider::maximumValue( int index )
     sql += QString( " WHERE %1" ).arg( mSubsetString );
   }
 
-  OGRLayerH l = OGR_DS_ExecuteSQL( ogrDataSource, mEncoding->fromUnicode( sql ).data(), NULL, "SQL" );
+  OGRLayerH l = OGR_DS_ExecuteSQL( ogrDataSource, TO8( sql ), NULL, "SQL" );
   if ( l == 0 )
     return QgsVectorDataProvider::maximumValue( index );