fix an issue I found where primshapes weren't every being removed

because of a logic error.
attempt to speed up deletes a bit by batching up all the primitem
deletes and primshape deletes into single delete statements.  This
removes the lock/release/lock/release/lock/release for loop.

OpenSim/Data/MySQL/MySQLRegionData.cs

@@ -300,17 +300,19 @@ namespace OpenSim.Data.MySQL
                     reader.Close();
                 }
 
-                foreach (UUID uuid in uuids)
-                    RemoveItems(uuid);
-
+                // delete the main prims
                 cmd.CommandText = "delete from prims where SceneGroupID= ?UUID";
-
-                ExecuteNonQuery(cmd);
-
-                cmd.CommandText = "delete from primshapes where UUID = ?UUID";
-
                 ExecuteNonQuery(cmd);
                 cmd.Dispose();
+
+                // there is no way this should be < 1 unless there is
+                // a very corrupt database, but in that case be extra
+                // safe anyway.
+                if (uuids.Count > 0) 
+                {
+                    RemoveShapes(uuids);
+                    RemoveItems(uuids);
+                }
             }
         }
 
@@ -335,6 +337,77 @@ namespace OpenSim.Data.MySQL
             }
         }
 
+
+        /// <summary>
+        /// Remove all persisted shapes for a list of prims
+        /// The caller must acquire the necessrary synchronization locks
+        /// </summary>
+        /// <param name="uuids">the list of UUIDs</param>
+        private void RemoveShapes(List<UUID> uuids)
+        {
+            lock (m_Connection)
+            {
+                string sql = "delete from primshapes where ";
+                MySqlCommand cmd = m_Connection.CreateCommand();
+                
+                for (int i = 0; i < uuids.Count; i++)
+                {
+                    if ((i + 1) == uuids.Count) 
+                    {// end of the list
+                        sql += "(UUID = ?UUID" + i + ")";
+                    }
+                    else
+                    {
+                        sql += "(UUID = ?UUID" + i + ") or ";
+                    }
+                }
+                cmd.CommandText = sql;
+
+                for (int i = 0; i < uuids.Count; i++)
+                {
+                    cmd.Parameters.AddWithValue("UUID" + i, uuids[i].ToString());
+                }
+
+                ExecuteNonQuery(cmd);
+                cmd.Dispose();
+            }
+        }
+
+        /// <summary>
+        /// Remove all persisted items for a list of prims
+        /// The caller must acquire the necessrary synchronization locks
+        /// </summary>
+        /// <param name="uuids">the list of UUIDs</param>
+        private void RemoveItems(List<UUID> uuids)
+        {
+            lock (m_Connection)
+            {
+                string sql = "delete from primitems where ";
+                MySqlCommand cmd = m_Connection.CreateCommand();
+                
+                for (int i = 0; i < uuids.Count; i++)
+                {
+                    if ((i + 1) == uuids.Count) 
+                    {// end of the list
+                        sql += "(PrimID = ?PrimID" + i + ")";
+                    }
+                    else
+                    {
+                        sql += "(PrimID = ?PrimID" + i + ") or ";
+                    }
+                }
+                cmd.CommandText = sql;
+
+                for (int i = 0; i < uuids.Count; i++)
+                {
+                    cmd.Parameters.AddWithValue("PrimID" + i, uuids[i].ToString());
+                }
+
+                ExecuteNonQuery(cmd);
+                cmd.Dispose();
+            }
+        }
+
         public List<SceneObjectGroup> LoadObjects(UUID regionUUID)
         {
             UUID lastGroupID = UUID.Zero;