diff --git a/ServerExplorer/TablaDesc.cs b/ServerExplorer/TablaDesc.cs
index 88d45a1..114254d 100644
--- a/ServerExplorer/TablaDesc.cs
+++ b/ServerExplorer/TablaDesc.cs
@@ -63,20 +63,21 @@ namespace ServerExplorer
 
             // Preparar comando y parametros
             da = new SqlDataAdapter(
-                "select	col.COLUMN_NAME as Columna, " +
-                "		col.DATA_TYPE as Tipo, " +
-                "		col.CHARACTER_MAXIMUM_LENGTH as Tamanho, " +
-                "		c.CONSTRAINT_TYPE as TipoClave " +
-                "	from INFORMATION_SCHEMA.COLUMNS as col " +
-                "	left join INFORMATION_SCHEMA.KEY_COLUMN_USAGE as k " +
-                "		on	col.COLUMN_NAME=k.COLUMN_NAME and " +
-                "			col.TABLE_NAME=k.TABLE_NAME and " +
+                "SELECT	col.COLUMN_NAME AS Columna, " +
+                "		col.DATA_TYPE AS Tipo, " +
+                "		col.CHARACTER_MAXIMUM_LENGTH AS Tamanho, " +
+                "		c.CONSTRAINT_TYPE AS TipoClave, " +
+                "		col.IS_NULLABLE AS Nullable " +
+                "	FROM INFORMATION_SCHEMA.COLUMNS AS col " +
+                "	LEFT JOIN INFORMATION_SCHEMA.KEY_COLUMN_USAGE AS k " +
+                "		ON	col.COLUMN_NAME=k.COLUMN_NAME AND " +
+                "			col.TABLE_NAME=k.TABLE_NAME AND " +
                 "			col.TABLE_SCHEMA=k.TABLE_SCHEMA " +
-                "	left join INFORMATION_SCHEMA.TABLE_CONSTRAINTS as c " +
-                "		on k.CONSTRAINT_NAME=c.CONSTRAINT_NAME " +
+                "	LEFT JOIN INFORMATION_SCHEMA.TABLE_CONSTRAINTS AS c " +
+                "		ON k.CONSTRAINT_NAME=c.CONSTRAINT_NAME " +
                 "	WHERE   col.TABLE_NAME=@nombreTabla AND " +
                 "           col.TABLE_SCHEMA=@nombreEsquema " +
-                "	order by col.ORDINAL_POSITION",
+                "	ORDER BY col.ORDINAL_POSITION",
                 cnx);
             prm = new SqlParameter("@nombreTabla", SqlDbType.VarChar, 100);
             prm.Value = nombre;
@@ -119,6 +120,8 @@ namespace ServerExplorer
                         col.Primaria = true;
                     }
                 }
+                string strNullable=((String)dr["Nullable"]).ToLower();
+                col.Nullable = (strNullable == "yes");
             }
         }
 
@@ -170,6 +173,14 @@ namespace ServerExplorer
             set { tamanho = value; }
         }
 
+        private bool nullable = false;
+        [XmlAttribute("Nullable")]
+        public bool Nullable
+        {
+            get { return nullable; }
+            set { nullable = value; }
+        }
+
         private bool primaria = false;
         [XmlAttribute("Primaria")]
         public bool Primaria