Support for TIMESTAMP columns holding NULL values. Unlike all other

column types TIMESTAMP is NOT NULL by default, so in order to have 
TIMESTAMP column holding NULL valaues you have to specify NULL as
one of its attributes (this needed for backward compatibility).

Main changes:
Replaced TABLE::timestamp_default_now/on_update_now members with
TABLE::timestamp_auto_set_type flag which is used everywhere
for determining if we should auto-set value of TIMESTAMP field 
during this operation or not. We are also use Field_timestamp::set_time()
instead of handler::update_timestamp() in handlers.

1 files changed, 4 insertions, 4 deletions

diff --git a/sql/ha_myisam.cc b/sql/ha_myisam.cc
index 95a294764d3..729ec4c27eb 100644
--- a/sql/ha_myisam.cc
+++ b/sql/ha_myisam.cc
@@ -251,8 +251,8 @@ int ha_myisam::write_row(byte * buf)
   statistic_increment(ha_write_count,&LOCK_status);
 
   /* If we have a timestamp column, update it to the current time */
-  if (table->timestamp_default_now)
-    update_timestamp(buf+table->timestamp_default_now-1);
+  if (table->timestamp_field_type & TIMESTAMP_AUTO_SET_ON_INSERT)
+    table->timestamp_field->set_time();
 
   /*
     If we have an auto_increment column and we are writing a changed row
@@ -1070,8 +1070,8 @@ bool ha_myisam::is_crashed() const
 int ha_myisam::update_row(const byte * old_data, byte * new_data)
 {
   statistic_increment(ha_update_count,&LOCK_status);
-  if (table->timestamp_on_update_now)
-    update_timestamp(new_data+table->timestamp_on_update_now-1);
+  if (table->timestamp_field_type & TIMESTAMP_AUTO_SET_ON_UPDATE)
+    table->timestamp_field->set_time();
   return mi_update(file,old_data,new_data);
 }