A quicker way to delete list item versions

My requirement is to delete all the SPListItem versions except the first 25... so I have to start deleting from 26 or index 25. One of the SPListItem in a library has so many versions... may be more than 100k that the web interface is not able to show all the versions. The size of the database is almost 900GB.

I wrote this code but I think the issue is with the item.Versions property. It tries to load all the versions in memory

foreach (SPListItem item in library.Items)
{  
  foundMoreVersionsThanRequired = false;
  int tempVersionToKepp = howManyVersionsToKeep + 1;

  for (int i = 0; i <= tempVersionToKepp; i++)
  {
    SPListItemVersion objVersion = null;

    try
    {
       objVersion = item.Versions[i];
       if (objVersion != null && i == tempVersionToKepp)
       {
         foundMoreVersionsThanRequired = true;
         break;
       }
     }
     catch
     {
       foundMoreVersionsThanRequired = false;
       break;
     }
   }
   if (foundM开发者_Python百科oreVersionsThanRequired)
   {
     int tempIndex = howManyVersionsToKeep + 1;                     
     SPListItemVersion objVersion = null;
     do
     {
       try
       {
         objVersion = item.Versions[tempIndex];
         if (objVersion != null)
         {
           objVersion.Delete();
         }
         else
           break;
       }
       catch
       {
         break;
       }
     } while (true);
   }
   count++;
 }

I am positive that the issue is with "item.Versions" property. It seems that when you call item.Versions it loads all the objects in the memory and that is causing a lot of issues.

Any way to delete an SPListItem version directly?

why not just set the list to only keep 25 versions within SharePoint itself from the web?