DB operations now occur w/in transactions, added Open DB Form to tester

Delta.cs

@@ -1,4 +1,5 @@
 using DbTools.Model;
+using System;
 using System.Data;
 using System.Linq;
 using System.Text;
@@ -8,6 +9,7 @@ namespace DbTools {
     public class Delta {
         public string Db1Sql { get; set; }
         public string Db2Sql { get; set; }
+        public Exception LastError { get; private set; }
 
         public string BuildDelta(IDbConnection currentDb, IDbConnection newDb, bool removeUnusedTables = false, bool removeUnusedColumns = false, bool removeUnusedTriggers = true, bool removeUnusedIndexes = true) {
             Database db1 = new Database(currentDb, true);
@@ -44,9 +46,20 @@ namespace DbTools {
 
         public bool ApplyDelta(IDbConnection cn, string sql) {
             bool success = false;
-            using (var cmd = cn.CreateCommand()) {
-                cmd.CommandText = sql;
-                success = cmd.ExecuteNonQuery() > 0;
+            using (var transaction = cn.BeginTransaction()) {
+                try {
+                    using (var cmd = cn.CreateCommand()) {
+                        cmd.Transaction = transaction;
+                        cmd.CommandText = sql;
+                        cmd.ExecuteNonQuery();
+                    }
+                    transaction.Commit();
+                    success = true;
+                } catch (Exception ex) {
+                    transaction.Rollback();
+                    success = false;
+                    LastError = ex;
+                }
             }
             return success;
         }
@@ -70,6 +83,8 @@ namespace DbTools {
                 var table1 = db1.Tables[table2.TableName];
                 if (table1 == null) {
                     sb.AppendLine(table2.FullSql());
+                    sb.AppendLine("-- TODO : Insert records from existing database");
+                    sb.AppendLine("");
                 } else {
                     // Remove unused triggers if requested
                     if (removeUnusedTriggers) {
@@ -118,6 +133,10 @@ namespace DbTools {
                     }
                 }
             }
+
+            if (string.IsNullOrWhiteSpace(sb.ToString().Trim())) {
+                sb.AppendLine("-- BOTH DATABASES ARE EQUAL - NO CHANGES ARE REQUIRED --");
+            }
             return sb.ToString();
         }