No subject

uInt16 nId = ...;
try
{
    addColumTo_pCols(nId, ...);

    // some code that may throw
    (...)

    addColumnTo_m_aColumns(nId, ...);
}
catch (...)
{
    removeColumn(nId);
    throw;
}

And actually, now that this is clear in my mind, I think the patch
should be, for more clarity:

 void DbGridControl::RemoveColumn(sal_uInt16 nId)
 {
+    DbGridControl_Base::RemoveColumn(nId);
+
     sal_uInt16 nIndex = GetModelColumnPos(nId);
     if (nIndex == GRID_COLUMN_NOT_FOUND)
         return;
 
-    DbGridControl_Base::RemoveColumn(nId);
-
     delete m_aColumns[ nIndex ];
     DbGridColumns::iterator it = m_aColumns.begin();
     ::std::advance( it, nIndex );


This makes it more clear that the call to
DbGridControl_Base::RemoveColumn and the result of
GetModelColumnPos(nId) are meant to be completely independent.

-- 
Lionel