[DBAL-42] MySQLPlatform::getAlterTableSQL() with regard with Doctrine Type Detection.

lib/Doctrine/DBAL/Platforms/MySqlPlatform.php

@@ -422,7 +422,9 @@ class MySqlPlatform extends AbstractPlatform
         }
 
         foreach ($diff->addedColumns AS $fieldName => $column) {
-            $queryParts[] = 'ADD ' . $this->getColumnDeclarationSQL($column->getQuotedName($this), $column->toArray());
+            $columnArray = $column->toArray();
+            $columnArray['comment'] = $this->getColumnComment($column);
+            $queryParts[] = 'ADD ' . $this->getColumnDeclarationSQL($column->getQuotedName($this), $columnArray);
         }
 
         foreach ($diff->removedColumns AS $column) {
@@ -432,13 +434,17 @@ class MySqlPlatform extends AbstractPlatform
         foreach ($diff->changedColumns AS $columnDiff) {
             /* @var $columnDiff Doctrine\DBAL\Schema\ColumnDiff */
             $column = $columnDiff->column;
+            $columnArray = $column->toArray();
+            $columnArray['comment'] = $this->getColumnComment($column);
             $queryParts[] =  'CHANGE ' . ($columnDiff->oldColumnName) . ' '
-                    . $this->getColumnDeclarationSQL($column->getQuotedName($this), $column->toArray());
+                    . $this->getColumnDeclarationSQL($column->getQuotedName($this), $columnArray);
         }
 
         foreach ($diff->renamedColumns AS $oldColumnName => $column) {
+            $columnArray = $column->toArray();
+            $columnArray['comment'] = $this->getColumnComment($column);
             $queryParts[] =  'CHANGE ' . $oldColumnName . ' '
-                    . $this->getColumnDeclarationSQL($column->getQuotedName($this), $column->toArray());
+                    . $this->getColumnDeclarationSQL($column->getQuotedName($this), $columnArray);
         }
 
         $sql = array();