diff --git a/ceilometer/storage/sqlalchemy/migrate_repo/versions/025_alarm_use_floatingprecision.py b/ceilometer/storage/sqlalchemy/migrate_repo/versions/025_alarm_use_floatingprecision.py
new file mode 100644
index 000000000..3a3691c01
--- /dev/null
+++ b/ceilometer/storage/sqlalchemy/migrate_repo/versions/025_alarm_use_floatingprecision.py
@@ -0,0 +1,82 @@
+# -*- encoding: utf-8 -*-
+#
+# Copyright © 2013 eNovance SAS <licensing@enovance.com>
+#
+# Author: Mehdi Abaakouk <mehdi.abaakouk@enovance.com>
+#
+# Licensed under the Apache License, Version 2.0 (the "License"); you may
+# not use this file except in compliance with the License. You may obtain
+# a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+# License for the specific language governing permissions and limitations
+# under the License.
+
+import sqlalchemy as sa
+
+from ceilometer.storage.sqlalchemy import models
+
+
+def _paged(query, size):
+    offset = 0
+    while True:
+        page = query.offset(offset).limit(size).execute()
+        if page.rowcount <= 0:
+            # There are no more rows
+            break
+        for row in page:
+            yield row
+        offset += size
+
+
+def _convert_data_type(table, col, from_t, to_t, pk_attr='id'):
+    temp_col_n = 'convert_data_type_temp_col'
+    # Override column we're going to convert with from_t, since the type we're
+    # replacing could be custom and we need to tell SQLALchemy how to perform
+    # CRUD operations with it.
+    table = sa.Table(table.name, table.metadata, sa.Column(col, from_t),
+                     extend_existing=True)
+    sa.Column(temp_col_n, to_t).create(table)
+
+    key_attr = getattr(table.c, pk_attr)
+    orig_col = getattr(table.c, col)
+    new_col = getattr(table.c, temp_col_n)
+
+    query = sa.select([key_attr, orig_col])
+    for key, value in _paged(query, 1000):
+        table.update().where(key_attr == key)\
+            .values({temp_col_n: value}).execute()
+
+    orig_col.drop()
+    new_col.alter(name=col)
+
+
+to_convert = [
+    ('alarm', 'timestamp', 'id'),
+    ('alarm', 'state_timestamp', 'id'),
+    ('alarm_history', 'timestamp', 'alarm_id'),
+]
+
+
+def upgrade(migrate_engine):
+    if migrate_engine.name == 'mysql':
+        meta = sa.MetaData(bind=migrate_engine)
+        for table_name, col_name, pk_attr in to_convert:
+            table = sa.Table(table_name, meta, autoload=True)
+            _convert_data_type(table, col_name, sa.DateTime(),
+                               models.PreciseTimestamp(),
+                               pk_attr=pk_attr)
+
+
+def downgrade(migrate_engine):
+    if migrate_engine.name == 'mysql':
+        meta = sa.MetaData(bind=migrate_engine)
+        for table_name, col_name, pk_attr in to_convert:
+            table = sa.Table(table_name, meta, autoload=True)
+            _convert_data_type(table, col_name, models.PreciseTimestamp(),
+                               sa.DateTime(),
+                               pk_attr=pk_attr)
diff --git a/ceilometer/storage/sqlalchemy/models.py b/ceilometer/storage/sqlalchemy/models.py
index d3d3f2a1b..d1f05204c 100644
--- a/ceilometer/storage/sqlalchemy/models.py
+++ b/ceilometer/storage/sqlalchemy/models.py
@@ -22,7 +22,7 @@ import json
 import urlparse
 
 from oslo.config import cfg
-from sqlalchemy import Column, Integer, String, Table, ForeignKey, DateTime, \
+from sqlalchemy import Column, Integer, String, Table, ForeignKey, \
     Index, UniqueConstraint, BigInteger
 from sqlalchemy import Float, Boolean, Text
 from sqlalchemy.dialects.mysql import DECIMAL
@@ -265,13 +265,13 @@ class Alarm(Base):
     name = Column(Text)
     type = Column(String(50))
     description = Column(Text)
-    timestamp = Column(DateTime, default=timeutils.utcnow)
+    timestamp = Column(PreciseTimestamp, default=timeutils.utcnow)
 
     user_id = Column(String(255), ForeignKey('user.id'))
     project_id = Column(String(255), ForeignKey('project.id'))
 
     state = Column(String(255))
-    state_timestamp = Column(DateTime, default=timeutils.utcnow)
+    state_timestamp = Column(PreciseTimestamp, default=timeutils.utcnow)
 
     ok_actions = Column(JSONEncodedDict)
     alarm_actions = Column(JSONEncodedDict)
@@ -294,7 +294,7 @@ class AlarmChange(Base):
     user_id = Column(String(255), ForeignKey('user.id'))
     type = Column(String(20))
     detail = Column(Text)
-    timestamp = Column(DateTime, default=timeutils.utcnow)
+    timestamp = Column(PreciseTimestamp, default=timeutils.utcnow)
 
 
 class EventType(Base):