diff --git a/field_options.go b/field_options.go
index 107afaac..f7acd5a6 100644
--- a/field_options.go
+++ b/field_options.go
@@ -51,30 +51,34 @@ var (
 			nullable := false
 			if strings.HasPrefix(ft, "*") {
 				nullable = true
-				ft = ft[1:]
+				ft = strings.TrimLeft(ft, "*")
 			}
 			if !all && !nullable {
 				return f
 			}
 
 			switch ft {
+			case "time.Time":
+				ft = "sql.NullTime"
 			case "string":
-				f.Type = "sql.NullString"
+				ft = "sql.NullString"
 			case "int", "int64", "uint", "uint32", "uint64":
-				f.Type = "sql.NullInt64"
+				ft = "sql.NullInt64"
 			case "uint16", "int32":
-				f.Type = "sql.NullInt32"
+				ft = "sql.NullInt32"
 			case "int8", "uint8", "int16":
-				f.Type = "sql.NullInt16"
+				ft = "sql.NullInt16"
 			case "byte":
-				f.Type = "sql.NullByte"
+				ft = "sql.NullByte"
 			case "float64", "float32":
-				f.Type = "sql.NullFloat64"
+				ft = "sql.NullFloat64"
 			case "bool":
-				f.Type = "sql.NullBool"
-			case "time.Time":
-				f.Type = "sql.NullTime"
+				ft = "sql.NullBool"
+			default:
+				return f
 			}
+			f.CustomGenType = f.GenType()
+			f.Type = ft
 			return f
 		}
 	}