From 41e9fda2dec8c3b672e5d26bccdc683553ae5549 Mon Sep 17 00:00:00 2001
From: Murray Hou <minglei84@126.com>
Date: Tue, 21 Jul 2015 15:38:21 +0800
Subject: [PATCH] Fixed [default value] For Mysql

The [default value] can'nt use [modify column] in mysql.
---
 .../Interpreters/MySqlCommandInterpreter.cs   | 28 ++++++++++++++++---
 1 file changed, 24 insertions(+), 4 deletions(-)

diff --git a/src/Orchard/Data/Migration/Interpreters/MySqlCommandInterpreter.cs b/src/Orchard/Data/Migration/Interpreters/MySqlCommandInterpreter.cs
index df3b1bd3a..33b9de478 100644
--- a/src/Orchard/Data/Migration/Interpreters/MySqlCommandInterpreter.cs
+++ b/src/Orchard/Data/Migration/Interpreters/MySqlCommandInterpreter.cs
@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.Data;
 using System.Text;
 using NHibernate.Dialect;
@@ -34,6 +35,7 @@ namespace Orchard.Data.Migration.Interpreters {
             builder.AppendFormat("alter table {0} modify column {1} ",
                             _dialectLazy.Value.QuoteForTableName(PrefixTableName(command.TableName)),
                             _dialectLazy.Value.QuoteForColumnName(command.ColumnName));
+            var initLength = builder.Length;
 
             // type
             if (command.DbType != DbType.Object) {
@@ -46,13 +48,31 @@ namespace Orchard.Data.Migration.Interpreters {
             }
 
             // [default value]
+            var builder2 = new StringBuilder();
+
+            builder2.AppendFormat("alter table {0} alter column {1} ",
+                            _dialectLazy.Value.QuoteForTableName(PrefixTableName(command.TableName)),
+                            _dialectLazy.Value.QuoteForColumnName(command.ColumnName));
+            var initLength2 = builder2.Length;
+            
             if (command.Default != null) {
-                builder.Append(" set default ").Append(DefaultDataMigrationInterpreter.ConvertToSqlValue(command.Default)).Append(" ");
+                builder2.Append(" set default ").Append(DefaultDataMigrationInterpreter.ConvertToSqlValue(command.Default)).Append(" ");
             }
 
-            return new [] {
-                builder.ToString()
-            };
+            // result
+            var result = new List<string>();
+
+            if (builder.Length > initLength)
+            {
+                result.Add(builder.ToString());
+            }
+
+            if (builder2.Length > initLength2)
+            {
+                result.Add(builder2.ToString());
+            }
+
+            return result.ToArray();
         }
 
         private string PrefixTableName(string tableName) {