From 02be0cb4d1d7399cacaa8742a385f84634ca5db6 Mon Sep 17 00:00:00 2001
From: Even Rouault <even.rouault@spatialys.com>
Date: Wed, 4 May 2016 15:51:33 +0200
Subject: [PATCH] QgsOgrProvider::addAttributes(): call invalidateConnections()
 for MapInfo

---
 src/providers/ogr/qgsogrprovider.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/src/providers/ogr/qgsogrprovider.cpp b/src/providers/ogr/qgsogrprovider.cpp
index 6f707807649..6731bb9062b 100644
--- a/src/providers/ogr/qgsogrprovider.cpp
+++ b/src/providers/ogr/qgsogrprovider.cpp
@@ -1212,6 +1212,13 @@ bool QgsOgrProvider::addAttributes( const QList<QgsField> &attributes )
   if ( !doInitialActionsForEdition() )
     return false;
 
+  if ( ogrDriverName == "MapInfo File" )
+  {
+    // adding attributes in mapinfo requires to be able to delete the .dat file
+    // so drop any cached connections.
+    QgsOgrConnPool::instance()->invalidateConnections( filePath() );
+  }
+
   bool returnvalue = true;
 
   for ( QList<QgsField>::const_iterator iter = attributes.begin(); iter != attributes.end(); ++iter )