Fixing unique constraint in SqlaTable model

caravel/migrations/versions/b4456560d4f3_change_table_unique_constraint.py

@@ -0,0 +1,25 @@
+"""change_table_unique_constraint
+
+Revision ID: b4456560d4f3
+Revises: bb51420eaf83
+Create Date: 2016-04-15 08:31:26.249591
+
+"""
+
+# revision identifiers, used by Alembic.
+revision = 'b4456560d4f3'
+down_revision = 'bb51420eaf83'
+
+from alembic import op
+
+
+def upgrade():
+    op.drop_constraint(
+        u'tables_table_name_key', 'tables', type_='unique')
+    op.create_unique_constraint(
+        u'_customer_location_uc', 'tables',
+        ['database_id', 'schema', 'table_name'])
+
+
+def downgrade():
+    op.drop_constraint(u'_customer_location_uc', 'tables', type_='unique')

caravel/models.py

@@ -406,7 +406,7 @@ class SqlaTable(Model, Queryable, AuditMixinNullable):
 
     __tablename__ = 'tables'
     id = Column(Integer, primary_key=True)
-    table_name = Column(String(250), unique=True)
+    table_name = Column(String(250))
     main_dttm_col = Column(String(250))
     description = Column(Text)
     default_endpoint = Column(Text)
@@ -422,6 +422,11 @@ class SqlaTable(Model, Queryable, AuditMixinNullable):
 
     baselink = "tablemodelview"
 
+    __table_args__ = (
+        sqla.UniqueConstraint(
+            'database_id', 'schema', 'table_name',
+            name='_customer_location_uc'),)
+
     def __repr__(self):
         return self.table_name