- use provide_metadata for new unique constraint / index tests

- add a test for PG reflection of unique index without any unique
constraint
- for PG, don't include 'duplicates_constraint' in the entry
if the index does not actually mirror a constraint
- use a distinct method for unique constraint reflection within table
- catch unique constraint not implemented condition; this may
be within some dialects and also is expected to be supported by
Alembic tests
- migration + changelogs for #3184
- add individual doc notes as well to MySQL, Postgreql
fixes #3184

1 files changed, 14 insertions, 1 deletions

diff --git a/lib/sqlalchemy/engine/reflection.py b/lib/sqlalchemy/engine/reflection.py
index 15c2dd195..2a1def86a 100644
--- a/lib/sqlalchemy/engine/reflection.py
+++ b/lib/sqlalchemy/engine/reflection.py
@@ -508,6 +508,10 @@ class Inspector(object):
             table_name, schema, table, cols_by_orig_name,
             include_columns, exclude_columns, reflection_options)
 
+        self._reflect_unique_constraints(
+            table_name, schema, table, cols_by_orig_name,
+            include_columns, exclude_columns, reflection_options)
+
     def _reflect_column(
         self, table, col_d, include_columns,
             exclude_columns, cols_by_orig_name):
@@ -665,8 +669,17 @@ class Inspector(object):
 
             sa_schema.Index(name, *idx_cols, **dict(unique=unique))
 
+    def _reflect_unique_constraints(
+        self, table_name, schema, table, cols_by_orig_name,
+            include_columns, exclude_columns, reflection_options):
+
         # Unique Constraints
-        constraints = self.get_unique_constraints(table_name, schema)
+        try:
+            constraints = self.get_unique_constraints(table_name, schema)
+        except NotImplementedError:
+            # optional dialect feature
+            return
+
         for const_d in constraints:
             conname = const_d['name']
             columns = const_d['column_names']