From a9dc29d79f2b013006a6a5198fc8f925da27b4cb Mon Sep 17 00:00:00 2001
From: gordon chung <chungg@ca.ibm.com>
Date: Wed, 28 May 2014 12:39:04 -0400
Subject: [PATCH] clean up sample index

- ensure foreign key columns are indexed (InnoDB adds these
indices implicitly so make sure index doesn't already exist)

Change-Id: Ia40c226ffea54cb07980864f0df1cb186dafd352
---
 .../versions/037_sample_index_cleanup.py      | 54 +++++++++++++++++++
 ceilometer/storage/sqlalchemy/models.py       |  1 +
 2 files changed, 55 insertions(+)
 create mode 100644 ceilometer/storage/sqlalchemy/migrate_repo/versions/037_sample_index_cleanup.py

diff --git a/ceilometer/storage/sqlalchemy/migrate_repo/versions/037_sample_index_cleanup.py b/ceilometer/storage/sqlalchemy/migrate_repo/versions/037_sample_index_cleanup.py
new file mode 100644
index 000000000..827676c55
--- /dev/null
+++ b/ceilometer/storage/sqlalchemy/migrate_repo/versions/037_sample_index_cleanup.py
@@ -0,0 +1,54 @@
+# 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.
+
+from migrate import ForeignKeyConstraint
+import sqlalchemy as sa
+
+
+class ForeignKeyHandle():
+    def __init__(self, meta):
+        sample = sa.Table('sample', meta, autoload=True)
+        meter = sa.Table('meter', meta, autoload=True)
+        self.sample_params = {'columns': [sample.c.meter_id],
+                              'refcolumns': [meter.c.id]}
+        if meta.bind.engine.name == 'mysql':
+            self.sample_params['name'] = "fk_sample_meter_id"
+
+    def __enter__(self):
+        ForeignKeyConstraint(**self.sample_params).drop()
+
+    def __exit__(self, type, value, traceback):
+        ForeignKeyConstraint(**self.sample_params).create()
+
+
+def upgrade(migrate_engine):
+    if migrate_engine.name == 'sqlite':
+        return
+    meta = sa.MetaData(bind=migrate_engine)
+    sample = sa.Table('sample', meta, autoload=True)
+
+    with ForeignKeyHandle(meta):
+        # remove stray indexes implicitly created by InnoDB
+        for index in sample.indexes:
+            if index.name in ['fk_sample_meter_id', 'fk_sample_resource_id']:
+                index.drop()
+        sa.Index('ix_sample_meter_id', sample.c.meter_id).create()
+
+
+def downgrade(migrate_engine):
+    if migrate_engine.name == 'sqlite':
+        return
+    meta = sa.MetaData(bind=migrate_engine)
+    sample = sa.Table('sample', meta, autoload=True)
+
+    with ForeignKeyHandle(meta):
+        sa.Index('ix_sample_meter_id', sample.c.meter_id).drop()
diff --git a/ceilometer/storage/sqlalchemy/models.py b/ceilometer/storage/sqlalchemy/models.py
index e820d5d36..696d9431a 100644
--- a/ceilometer/storage/sqlalchemy/models.py
+++ b/ceilometer/storage/sqlalchemy/models.py
@@ -168,6 +168,7 @@ class Sample(Base):
         Index('ix_sample_timestamp', 'timestamp'),
         Index('ix_sample_user_id', 'user_id'),
         Index('ix_sample_project_id', 'project_id'),
+        Index('ix_sample_meter_id', 'meter_id')
     )
     id = Column(Integer, primary_key=True)
     meter_id = Column(Integer, ForeignKey('meter.id'))