Remove downgrade

Removed downgrade from all existing migrations.
Modified a test that verifies that no migrations have a downgrade.
Modified test _walk_versions to only do upgrades.
Removed exceptions from pylint.config

Related cross-project spec: https://review.openstack.org/152337
Closes-Bug: #1434103

Change-Id: I9a7c87ae3f4e2eff3a4a6df881d086d52062dbba

40 files changed, 0 insertions, 433 deletions

diff --git a/trove/db/sqlalchemy/api.py b/trove/db/sqlalchemy/api.py
index b5aa3be9..324dcd32 100644
--- a/trove/db/sqlalchemy/api.py
+++ b/trove/db/sqlalchemy/api.py
@@ -107,10 +107,6 @@ def db_upgrade(options, version=None, repo_path=None):
     migration.upgrade(options, version, repo_path)
 
 
-def db_downgrade(options, version, repo_path=None):
-    migration.downgrade(options, version, repo_path)
-
-
 def db_reset(options, *plugins):
     drop_db(options)
     db_sync(options)
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/001_base_schema.py b/trove/db/sqlalchemy/migrate_repo/versions/001_base_schema.py
index 74113452..2db50099 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/001_base_schema.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/001_base_schema.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import Integer
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
@@ -44,8 +43,3 @@ instances = Table(
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([instances])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([instances])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/002_service_images.py b/trove/db/sqlalchemy/migrate_repo/versions/002_service_images.py
index b82eb5c5..3d1a1b01 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/002_service_images.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/002_service_images.py
@@ -17,7 +17,6 @@ from sqlalchemy.schema import Column
 from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
@@ -35,8 +34,3 @@ service_images = Table(
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([service_images])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([service_images])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/003_service_statuses.py b/trove/db/sqlalchemy/migrate_repo/versions/003_service_statuses.py
index 76f04955..416caa6c 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/003_service_statuses.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/003_service_statuses.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import Integer
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
@@ -39,8 +38,3 @@ service_statuses = Table(
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([service_statuses])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([service_statuses])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/004_root_enabled.py b/trove/db/sqlalchemy/migrate_repo/versions/004_root_enabled.py
index 6fd6f126..478e54b2 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/004_root_enabled.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/004_root_enabled.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
@@ -37,8 +36,3 @@ root_enabled_history = Table(
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([root_enabled_history])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([root_enabled_history])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/005_heartbeat.py b/trove/db/sqlalchemy/migrate_repo/versions/005_heartbeat.py
index 57aa7f7b..efe4783e 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/005_heartbeat.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/005_heartbeat.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
@@ -36,8 +35,3 @@ agent_heartbeats = Table(
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([agent_heartbeats])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([agent_heartbeats])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/006_dns_records.py b/trove/db/sqlalchemy/migrate_repo/versions/006_dns_records.py
index 79d554e6..46f97999 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/006_dns_records.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/006_dns_records.py
@@ -17,7 +17,6 @@ from sqlalchemy.schema import Column
 from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
@@ -34,8 +33,3 @@ dns_records = Table(
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([dns_records])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([dns_records])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/007_add_volume_flavor.py b/trove/db/sqlalchemy/migrate_repo/versions/007_add_volume_flavor.py
index 829a8a4b..3ee23757 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/007_add_volume_flavor.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/007_add_volume_flavor.py
@@ -31,14 +31,3 @@ def upgrade(migrate_engine):
 
     instances.create_column(flavor_id)
     instances.create_column(volume_size)
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    # drop column:
-    instances = Table('instances', meta, autoload=True)
-
-    instances.drop_column('flavor_id')
-    instances.drop_column('volume_size')
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/008_add_instance_fields.py b/trove/db/sqlalchemy/migrate_repo/versions/008_add_instance_fields.py
index dfd60597..eb722e06 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/008_add_instance_fields.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/008_add_instance_fields.py
@@ -27,14 +27,3 @@ def upgrade(migrate_engine):
     instances = Table('instances', meta, autoload=True)
     instances.create_column(Column('tenant_id', String(36), nullable=True))
     instances.create_column(Column('server_status', String(64)))
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    # drop column:
-    instances = Table('instances', meta, autoload=True)
-
-    instances.drop_column('tenant_id')
-    instances.drop_column('server_status')
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/009_add_deleted_flag_to_instances.py b/trove/db/sqlalchemy/migrate_repo/versions/009_add_deleted_flag_to_instances.py
index 69d22936..f5668df2 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/009_add_deleted_flag_to_instances.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/009_add_deleted_flag_to_instances.py
@@ -28,13 +28,3 @@ def upgrade(migrate_engine):
     instances = Table('instances', meta, autoload=True)
     instances.create_column(Column('deleted', Boolean()))
     instances.create_column(Column('deleted_at', DateTime()))
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    # drop column:
-    instances = Table('instances', meta, autoload=True)
-    instances.drop_column('deleted')
-    instances.drop_column('deleted_at')
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/010_add_usage.py b/trove/db/sqlalchemy/migrate_repo/versions/010_add_usage.py
index 0e4fdfc2..b55a2056 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/010_add_usage.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/010_add_usage.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import Integer
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
@@ -44,8 +43,3 @@ usage_events = Table(
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([usage_events])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([usage_events])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/011_quota.py b/trove/db/sqlalchemy/migrate_repo/versions/011_quota.py
index 3cd4d3d6..616e1803 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/011_quota.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/011_quota.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import UniqueConstraint
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import Integer
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
@@ -60,8 +59,3 @@ reservations = Table('reservations', meta,
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([quotas, quota_usages, reservations])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([quotas, quota_usages, reservations])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/012_backup.py b/trove/db/sqlalchemy/migrate_repo/versions/012_backup.py
index 5b32724c..6da31474 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/012_backup.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/012_backup.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import MetaData
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import Float
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
@@ -46,8 +45,3 @@ backups = Table('backups', meta,
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([backups, ])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([backups, ])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/013_add_security_group_artifacts.py b/trove/db/sqlalchemy/migrate_repo/versions/013_add_security_group_artifacts.py
index 65679e23..499be5fd 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/013_add_security_group_artifacts.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/013_add_security_group_artifacts.py
@@ -20,7 +20,6 @@ from sqlalchemy.schema import MetaData
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import Integer
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
@@ -88,9 +87,3 @@ def upgrade(migrate_engine):
     )
     create_tables([security_groups, security_group_rules,
                    security_group_instance_associations])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([security_group_instance_associations,
-                 security_group_rules, security_groups])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/014_update_instance_flavor_id.py b/trove/db/sqlalchemy/migrate_repo/versions/014_update_instance_flavor_id.py
index 66b118f3..23eb5749 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/014_update_instance_flavor_id.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/014_update_instance_flavor_id.py
@@ -15,7 +15,6 @@
 from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import Integer
-from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
 
@@ -33,13 +32,3 @@ def upgrade(migrate_engine):
         instances = Table('instances', meta, autoload=True)
         # modify column
         instances.c.flavor_id.alter(type=Integer())
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-    # int->char casts in pgsql still work fine without any USING clause,
-    #  so downgrade is not affected.
-    # modify column:
-    instances = Table('instances', meta, autoload=True)
-    instances.c.flavor_id.alter(type=String(36))
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/015_add_service_type.py b/trove/db/sqlalchemy/migrate_repo/versions/015_add_service_type.py
index aa6132f0..a5b41fe4 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/015_add_service_type.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/015_add_service_type.py
@@ -26,11 +26,3 @@ def upgrade(migrate_engine):
     service_type = Column('service_type', String(36))
     instances.create_column(service_type)
     instances.update().values({'service_type': 'mysql'}).execute()
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-    # modify column:
-    instances = Table('instances', meta, autoload=True)
-    instances.drop_column('service_type')
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/016_add_datastore_type.py b/trove/db/sqlalchemy/migrate_repo/versions/016_add_datastore_type.py
index cec628a7..9bfd834c 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/016_add_datastore_type.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/016_add_datastore_type.py
@@ -19,10 +19,8 @@ from sqlalchemy.schema import UniqueConstraint
 
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
-from trove.db.sqlalchemy import utils as db_utils
 
 
 meta = MetaData()
@@ -62,23 +60,3 @@ def upgrade(migrate_engine):
     # Table 'service_images' is deprecated since this version.
     # Leave it for few releases.
     # drop_tables([service_images])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    instances = Table('instances', meta, autoload=True)
-    constraint_names = db_utils.get_foreign_key_constraint_names(
-        engine=migrate_engine,
-        table='instances',
-        columns=['datastore_version_id'],
-        ref_table='datastore_versions',
-        ref_columns=['id'])
-    db_utils.drop_foreign_key_constraints(
-        constraint_names=constraint_names,
-        columns=[instances.c.datastore_version_id],
-        ref_columns=[datastore_versions.c.id])
-    instances.drop_column('datastore_version_id')
-    service_type = Column('service_type', String(36))
-    instances.create_column(service_type)
-    instances.update().values({'service_type': 'mysql'}).execute()
-    drop_tables([datastore_versions, datastores])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/017_update_datastores.py b/trove/db/sqlalchemy/migrate_repo/versions/017_update_datastores.py
index a043b290..68383260 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/017_update_datastores.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/017_update_datastores.py
@@ -46,18 +46,3 @@ def upgrade(migrate_engine):
 
     # drop column from datastores
     datastores.drop_column('manager')
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    datastores = Table('datastores', meta, autoload=True)
-    datastore_versions = Table('datastore_versions', meta, autoload=True)
-
-    # drop column from datastore_versions
-    datastore_versions.drop_column('manager')
-
-    # add column to datastores
-    manager = Column('manager', String(255))
-    datastores.create_column(manager)
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/018_datastore_versions_fix.py b/trove/db/sqlalchemy/migrate_repo/versions/018_datastore_versions_fix.py
index dbb5ebaa..5d05db94 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/018_datastore_versions_fix.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/018_datastore_versions_fix.py
@@ -23,11 +23,3 @@ def upgrade(migrate_engine):
     datastore_versions = Table('datastore_versions', meta, autoload=True)
     # modify column
     datastore_versions.c.name.alter(unique=False)
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-    # modify column:
-    datastore_versions = Table('datastore_versions', meta, autoload=True)
-    datastore_versions.c.name.alter(unique=True)
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/019_datastore_fix.py b/trove/db/sqlalchemy/migrate_repo/versions/019_datastore_fix.py
index dab329aa..2a508f80 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/019_datastore_fix.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/019_datastore_fix.py
@@ -13,7 +13,6 @@
 #    under the License.
 
 from sqlalchemy.schema import MetaData
-from sqlalchemy.sql.expression import delete
 from sqlalchemy.sql.expression import insert
 from sqlalchemy.sql.expression import select
 from sqlalchemy.sql.expression import update
@@ -129,33 +128,3 @@ def upgrade(migrate_engine):
         constraint_names=constraint_names,
         columns=[instance_table.c.datastore_version_id],
         ref_columns=[datastore_versions_table.c.id])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-
-    instance_table = Table('instances', meta, autoload=True)
-
-    instance_table.c.datastore_version_id.alter(nullable=True)
-
-    update(
-        table=instance_table,
-        whereclause="datastore_version_id='%s'" % LEGACY_VERSION_ID,
-        values=dict(datastore_version_id=None)
-    ).execute()
-
-    datastores_table = Table('datastores',
-                             meta,
-                             autoload=True)
-    datastore_versions_table = Table('datastore_versions',
-                                     meta,
-                                     autoload=True)
-
-    delete(
-        table=datastore_versions_table,
-        whereclause="id='%s'" % LEGACY_VERSION_ID
-    ).execute()
-    delete(
-        table=datastores_table,
-        whereclause="id='%s'" % LEGACY_DATASTORE_ID
-    ).execute()
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/020_configurations.py b/trove/db/sqlalchemy/migrate_repo/versions/020_configurations.py
index 82e9b6a0..3b4fc1f2 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/020_configurations.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/020_configurations.py
@@ -20,10 +20,8 @@ from sqlalchemy.schema import MetaData
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
-from trove.db.sqlalchemy import utils as db_utils
 
 
 meta = MetaData()
@@ -59,20 +57,3 @@ def upgrade(migrate_engine):
     instances = Table('instances', meta, autoload=True)
     instances.create_column(Column('configuration_id', String(36),
                                    ForeignKey("configurations.id")))
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    instances = Table('instances', meta, autoload=True)
-    constraint_names = db_utils.get_foreign_key_constraint_names(
-        engine=migrate_engine,
-        table='instances',
-        columns=['configuration_id'],
-        ref_table='configurations',
-        ref_columns=['id'])
-    db_utils.drop_foreign_key_constraints(
-        constraint_names=constraint_names,
-        columns=[instances.c.configuration_id],
-        ref_columns=[configurations.c.id])
-    instances.drop_column('configuration_id')
-    drop_tables([configuration_parameters, configurations])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/021_conductor_last_seen.py b/trove/db/sqlalchemy/migrate_repo/versions/021_conductor_last_seen.py
index bfd52fdc..7bf683af 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/021_conductor_last_seen.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/021_conductor_last_seen.py
@@ -16,7 +16,6 @@ from sqlalchemy.schema import Column
 from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import Float
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
@@ -34,8 +33,3 @@ conductor_lastseen = Table(
 def upgrade(migrate_engine):
     meta.bind = migrate_engine
     create_tables([conductor_lastseen])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([conductor_lastseen])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/022_add_backup_parent_id.py b/trove/db/sqlalchemy/migrate_repo/versions/022_add_backup_parent_id.py
index f43b7371..62c2fdd8 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/022_add_backup_parent_id.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/022_add_backup_parent_id.py
@@ -26,12 +26,3 @@ def upgrade(migrate_engine):
     # add column:
     backups = Table('backups', meta, autoload=True)
     backups.create_column(Column('parent_id', String(36), nullable=True))
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    # drop column:
-    backups = Table('backups', meta, autoload=True)
-    backups.drop_column('parent_id')
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/023_add_instance_indexes.py b/trove/db/sqlalchemy/migrate_repo/versions/023_add_instance_indexes.py
index d1195e01..6a53eade 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/023_add_instance_indexes.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/023_add_instance_indexes.py
@@ -40,16 +40,3 @@ def upgrade(migrate_engine):
         deleted_idx.create()
     except OperationalError as e:
         logger.info(e)
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    instances = Table('instances', meta, autoload=True)
-
-    tenant_id_idx = Index("instances_tenant_id", instances.c.tenant_id)
-    tenant_id_idx.drop()
-
-    deleted_idx = Index("instances_deleted", instances.c.deleted)
-    deleted_idx.drop()
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/024_add_backup_indexes.py b/trove/db/sqlalchemy/migrate_repo/versions/024_add_backup_indexes.py
index 22be0a79..d4472a20 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/024_add_backup_indexes.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/024_add_backup_indexes.py
@@ -40,17 +40,3 @@ def upgrade(migrate_engine):
         backups_deleted_idx.create()
     except OperationalError as e:
         logger.info(e)
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    backups = Table('backups', meta, autoload=True)
-    backups_instance_id_idx = Index("backups_instance_id",
-                                    backups.c.instance_id)
-    backups_deleted_idx = Index("backups_deleted", backups.c.deleted)
-
-    meta.bind = migrate_engine
-    backups_instance_id_idx.drop()
-    backups_deleted_idx.drop()
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/025_add_service_statuses_indexes.py b/trove/db/sqlalchemy/migrate_repo/versions/025_add_service_statuses_indexes.py
index 62eefe8a..2f4d3e6e 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/025_add_service_statuses_indexes.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/025_add_service_statuses_indexes.py
@@ -33,12 +33,3 @@ def upgrade(migrate_engine):
         idx.create()
     except OperationalError as e:
         logger.info(e)
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    service_statuses = Table('service_statuses', meta, autoload=True)
-    idx = Index("service_statuses_instance_id", service_statuses.c.instance_id)
-    idx.drop()
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/026_datastore_versions_unique_fix.py b/trove/db/sqlalchemy/migrate_repo/versions/026_datastore_versions_unique_fix.py
index 364b3584..f37337b1 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/026_datastore_versions_unique_fix.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/026_datastore_versions_unique_fix.py
@@ -41,10 +41,3 @@ def upgrade(migrate_engine):
             uc.drop()
         except (OperationalError, InternalError) as e:
             logger.info(e)
-
-
-def downgrade(migrate_engine):
-    # we aren't going to recreate the index in this case for 2 reasons:
-    # 1. this column being unique was a bug in the first place
-    # 2. adding a unique index to a column that has duplicates will fail
-    pass
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/027_add_datastore_capabilities.py b/trove/db/sqlalchemy/migrate_repo/versions/027_add_datastore_capabilities.py
index 233ad3c8..1daae101 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/027_add_datastore_capabilities.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/027_add_datastore_capabilities.py
@@ -19,7 +19,6 @@ from sqlalchemy.schema import UniqueConstraint
 
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
@@ -54,8 +53,3 @@ def upgrade(migrate_engine):
     Table('datastores', meta, autoload=True)
     Table('datastore_versions', meta, autoload=True)
     create_tables([capabilities, capability_overrides])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([capability_overrides, capabilities])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/028_recreate_agent_heartbeat.py b/trove/db/sqlalchemy/migrate_repo/versions/028_recreate_agent_heartbeat.py
index d869ee36..2c4ea6d4 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/028_recreate_agent_heartbeat.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/028_recreate_agent_heartbeat.py
@@ -53,30 +53,3 @@ def upgrade(migrate_engine):
         logger.warn(e)
 
     create_tables([new_agent_heartbeats])
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    # new table with desired columns, indexes, and constraints
-    new_agent_heartbeats = Table('agent_heartbeats', meta, autoload=True)
-
-    try:
-        drop_tables([new_agent_heartbeats])
-    except OperationalError as e:
-        logger.warn("This table may have been dropped by some other means.")
-        logger.warn(e)
-
-    # reset the migrate_engine
-    meta = MetaData()
-    meta.bind = migrate_engine
-
-    # original table from migration 005_heartbeat.py
-    previous_agent_heartbeats = Table(
-        'agent_heartbeats', meta, Column('id', String(36), primary_key=True,
-                                         nullable=False),
-        Column('instance_id', String(36), nullable=False),
-        Column('updated_at', DateTime()), extend_existing=True)
-
-    create_tables([previous_agent_heartbeats])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/029_add_backup_datastore.py b/trove/db/sqlalchemy/migrate_repo/versions/029_add_backup_datastore.py
index 6f376471..c1156ba5 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/029_add_backup_datastore.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/029_add_backup_datastore.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
-from trove.db.sqlalchemy import utils as db_utils
 
 
 def upgrade(migrate_engine):
@@ -29,21 +28,3 @@ def upgrade(migrate_engine):
     datastore_version_id = Column('datastore_version_id', String(36),
                                   ForeignKey('datastore_versions.id'))
     backups.create_column(datastore_version_id)
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-    backups = Table('backups', meta, autoload=True)
-    datastore_versions = Table('datastore_versions', meta, autoload=True)
-    constraint_names = db_utils.get_foreign_key_constraint_names(
-        engine=migrate_engine,
-        table='backups',
-        columns=['datastore_version_id'],
-        ref_table='datastore_versions',
-        ref_columns=['id'])
-    db_utils.drop_foreign_key_constraints(
-        constraint_names=constraint_names,
-        columns=[backups.c.datastore_version_id],
-        ref_columns=[datastore_versions.c.id])
-    backups.drop_column('datastore_version_id')
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/030_add_master_slave.py b/trove/db/sqlalchemy/migrate_repo/versions/030_add_master_slave.py
index d031d167..6db24cd6 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/030_add_master_slave.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/030_add_master_slave.py
@@ -18,7 +18,6 @@ from sqlalchemy.schema import MetaData
 
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
-from trove.db.sqlalchemy import utils as db_utils
 
 
 COLUMN_NAME = 'slave_of_id'
@@ -31,20 +30,3 @@ def upgrade(migrate_engine):
     instances.create_column(
         Column(COLUMN_NAME, String(36), ForeignKey('instances.id')),
         nullable=True)
-
-
-def downgrade(migrate_engine):
-    meta = MetaData()
-    meta.bind = migrate_engine
-    instances = Table('instances', meta, autoload=True)
-    constraint_names = db_utils.get_foreign_key_constraint_names(
-        engine=migrate_engine,
-        table='instances',
-        columns=[COLUMN_NAME],
-        ref_table='instances',
-        ref_columns=['id'])
-    db_utils.drop_foreign_key_constraints(
-        constraint_names=constraint_names,
-        columns=[instances.c.slave_of_id],
-        ref_columns=[instances.c.id])
-    instances.drop_column(COLUMN_NAME)
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/031_add_timestamps_to_configurations.py b/trove/db/sqlalchemy/migrate_repo/versions/031_add_timestamps_to_configurations.py
index 4afd19f0..6f90ccf8 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/031_add_timestamps_to_configurations.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/031_add_timestamps_to_configurations.py
@@ -26,10 +26,3 @@ def upgrade(migrate_engine):
     updated = Column('updated', DateTime())
     configurations.create_column(created)
     configurations.create_column(updated)
-
-
-def downgrade(migrate_engine):
-    meta = MetaData(bind=migrate_engine)
-    configurations = Table('configurations', meta, autoload=True)
-    configurations.drop_column('created')
-    configurations.drop_column('updated')
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/032_clusters.py b/trove/db/sqlalchemy/migrate_repo/versions/032_clusters.py
index 1516906b..bfbc91f4 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/032_clusters.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/032_clusters.py
@@ -21,11 +21,9 @@ from sqlalchemy.schema import MetaData
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import Integer
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
-from trove.db.sqlalchemy import utils as db_utils
 
 
 meta = MetaData()
@@ -59,37 +57,3 @@ def upgrade(migrate_engine):
     instances.create_column(Column('type', String(64)))
     cluster_id_idx = Index("instances_cluster_id", instances.c.cluster_id)
     cluster_id_idx.create()
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-
-    datastore_versions = Table('datastore_versions', meta, autoload=True)
-    constraint_names = db_utils.get_foreign_key_constraint_names(
-        engine=migrate_engine,
-        table='clusters',
-        columns=['datastore_version_id'],
-        ref_table='datastore_versions',
-        ref_columns=['id'])
-    db_utils.drop_foreign_key_constraints(
-        constraint_names=constraint_names,
-        columns=[clusters.c.datastore_version_id],
-        ref_columns=[datastore_versions.c.id])
-
-    instances = Table('instances', meta, autoload=True)
-    constraint_names = db_utils.get_foreign_key_constraint_names(
-        engine=migrate_engine,
-        table='instances',
-        columns=['cluster_id'],
-        ref_table='clusters',
-        ref_columns=['id'])
-    db_utils.drop_foreign_key_constraints(
-        constraint_names=constraint_names,
-        columns=[instances.c.cluster_id],
-        ref_columns=[clusters.c.id])
-
-    instances.drop_column('cluster_id')
-    instances.drop_column('shard_id')
-    instances.drop_column('type')
-
-    drop_tables([clusters])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/033_datastore_parameters.py b/trove/db/sqlalchemy/migrate_repo/versions/033_datastore_parameters.py
index c88d807c..bee56629 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/033_datastore_parameters.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/033_datastore_parameters.py
@@ -21,7 +21,6 @@ from sqlalchemy.schema import UniqueConstraint
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
@@ -53,8 +52,3 @@ def upgrade(migrate_engine):
     meta.bind = migrate_engine
     Table('datastore_versions', meta, autoload=True)
     create_tables([datastore_configuration_parameters])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([datastore_configuration_parameters])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/034_change_task_description.py b/trove/db/sqlalchemy/migrate_repo/versions/034_change_task_description.py
index e96e9d85..7fc4b181 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/034_change_task_description.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/034_change_task_description.py
@@ -23,7 +23,3 @@ def upgrade(migrate_engine):
     meta.bind = migrate_engine
     instances = Table('instances', meta, autoload=True)
     instances.c.task_description.alter(type=String(255))
-
-
-def downgrade(migrate_engine):
-    pass
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/035_flavor_id_int_to_string.py b/trove/db/sqlalchemy/migrate_repo/versions/035_flavor_id_int_to_string.py
index 3a40bc88..3c461905 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/035_flavor_id_int_to_string.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/035_flavor_id_int_to_string.py
@@ -15,7 +15,6 @@
 
 from sqlalchemy.schema import MetaData
 
-from trove.db.sqlalchemy.migrate_repo.schema import Integer
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
@@ -27,9 +26,3 @@ def upgrade(migrate_engine):
     meta.bind = migrate_engine
     instances = Table('instances', meta, autoload=True)
     instances.c.flavor_id.alter(String(255))
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    instances = Table('instances', meta, autoload=True)
-    instances.c.flavor_id.alter(Integer())
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/036_add_datastore_version_metadata.py b/trove/db/sqlalchemy/migrate_repo/versions/036_add_datastore_version_metadata.py
index cad51486..e98674a2 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/036_add_datastore_version_metadata.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/036_add_datastore_version_metadata.py
@@ -21,7 +21,6 @@ from sqlalchemy.schema import UniqueConstraint
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 
@@ -54,8 +53,3 @@ def upgrade(migrate_engine):
     # creates datastore_version_metadata table
     Table('datastore_versions', meta, autoload=True)
     create_tables([datastore_version_metadata])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([datastore_version_metadata])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/037_modules.py b/trove/db/sqlalchemy/migrate_repo/versions/037_modules.py
index b3d61e00..ad264bf4 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/037_modules.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/037_modules.py
@@ -22,7 +22,6 @@ from sqlalchemy.schema import UniqueConstraint
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 from trove.db.sqlalchemy.migrate_repo.schema import Text
@@ -77,8 +76,3 @@ def upgrade(migrate_engine):
     meta.bind = migrate_engine
     Table('instances', meta, autoload=True)
     create_tables([modules, instance_modules])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([instance_modules, modules])
diff --git a/trove/db/sqlalchemy/migrate_repo/versions/038_instance_faults.py b/trove/db/sqlalchemy/migrate_repo/versions/038_instance_faults.py
index 49b4570c..fe341143 100644
--- a/trove/db/sqlalchemy/migrate_repo/versions/038_instance_faults.py
+++ b/trove/db/sqlalchemy/migrate_repo/versions/038_instance_faults.py
@@ -21,7 +21,6 @@ from sqlalchemy.schema import MetaData
 from trove.db.sqlalchemy.migrate_repo.schema import Boolean
 from trove.db.sqlalchemy.migrate_repo.schema import create_tables
 from trove.db.sqlalchemy.migrate_repo.schema import DateTime
-from trove.db.sqlalchemy.migrate_repo.schema import drop_tables
 from trove.db.sqlalchemy.migrate_repo.schema import String
 from trove.db.sqlalchemy.migrate_repo.schema import Table
 from trove.db.sqlalchemy.migrate_repo.schema import Text
@@ -49,8 +48,3 @@ def upgrade(migrate_engine):
     meta.bind = migrate_engine
     Table('instances', meta, autoload=True)
     create_tables([instance_faults])
-
-
-def downgrade(migrate_engine):
-    meta.bind = migrate_engine
-    drop_tables([instance_faults])
diff --git a/trove/db/sqlalchemy/migration.py b/trove/db/sqlalchemy/migration.py
index 134226a8..84b42518 100644
--- a/trove/db/sqlalchemy/migration.py
+++ b/trove/db/sqlalchemy/migration.py
@@ -64,22 +64,6 @@ def upgrade(options, version=None, repo_path=None):
     return versioning_api.upgrade(sql_connection, repo_path, version)
 
 
-def downgrade(options, version, repo_path=None):
-    """Downgrade the database's current migration level.
-
-    :param options: options dict
-    :param version: version to downgrade to
-    :retval version number
-
-    """
-    db_version(options, repo_path)  # Ensure db is under migration control
-    repo_path = get_migrate_repo_path(repo_path)
-    sql_connection = options['database']['connection']
-    logger.info("Downgrading %(sql_connection)s to version %(version)s" %
-                {'sql_connection': sql_connection, 'version': version})
-    return versioning_api.downgrade(sql_connection, repo_path, version)
-
-
 def version_control(options, repo_path=None):
     """Place a database under migration control.