From ef654af35ab2443172eb79e6f279792b72980539 Mon Sep 17 00:00:00 2001
From: Mike Bayer <mike_mp@zzzcomputing.com>
Date: Fri, 20 May 2011 17:53:13 -0400
Subject: [PATCH] - Fixed bug affecting PG 9 whereby index reflection would
 fail if against a column whose name had changed.  [ticket:2141].  Also in
 0.6.8.

---
 CHANGES                                    |  4 +++
 lib/sqlalchemy/dialects/postgresql/base.py | 30 +++++++++++++++++-----
 test/dialect/test_postgresql.py            | 22 ++++++++++++++++
 3 files changed, 49 insertions(+), 7 deletions(-)

diff --git a/CHANGES b/CHANGES
index ee3183d18d..7863daa8c8 100644
--- a/CHANGES
+++ b/CHANGES
@@ -135,6 +135,10 @@ CHANGES
   - Fixed the psycopg2_version parsing in the 
     psycopg2 dialect.
 
+  - Fixed bug affecting PG 9 whereby index reflection
+    would fail if against a column whose name
+    had changed.  [ticket:2141].  Also in 0.6.8.
+
 - mssql
   - Fixed bug in MSSQL dialect whereby the aliasing
     applied to a schema-qualified table would leak
diff --git a/lib/sqlalchemy/dialects/postgresql/base.py b/lib/sqlalchemy/dialects/postgresql/base.py
index 7fdd74628f..3193cde9ed 100644
--- a/lib/sqlalchemy/dialects/postgresql/base.py
+++ b/lib/sqlalchemy/dialects/postgresql/base.py
@@ -1308,16 +1308,31 @@ class PGDialect(default.DefaultDialect):
     def get_indexes(self, connection, table_name, schema, **kw):
         table_oid = self.get_table_oid(connection, table_name, schema,
                                        info_cache=kw.get('info_cache'))
+
         IDX_SQL = """
-          SELECT c.relname, i.indisunique, i.indexprs, i.indpred,
-            a.attname
-          FROM pg_index i, pg_class c, pg_attribute a
-          WHERE i.indrelid = :table_oid AND i.indexrelid = c.oid
-            AND a.attrelid = i.indexrelid AND i.indisprimary = 'f'
-          ORDER BY c.relname, a.attnum
+          SELECT
+              i.relname as relname,
+              ix.indisunique, ix.indexprs, ix.indpred,
+              a.attname
+          FROM
+              pg_class t 
+                    join pg_index ix on t.oid = ix.indrelid
+                    join pg_class i on i.oid=ix.indexrelid
+                    left outer join 
+                        pg_attribute a 
+                        on t.oid=a.attrelid and a.attnum=ANY(ix.indkey)
+          WHERE
+              t.relkind = 'r'
+              and t.oid = :table_oid
+              and ix.indisprimary = 'f'
+          ORDER BY
+              t.relname,
+              i.relname
         """
+
         t = sql.text(IDX_SQL, typemap={'attname':sqltypes.Unicode})
         c = connection.execute(t, table_oid=table_oid)
+
         index_names = {}
         indexes = []
         sv_idx_name = None
@@ -1343,7 +1358,8 @@ class PGDialect(default.DefaultDialect):
                 indexes.append(index_d)
                 index_names[idx_name] = index_d
             index_d['name'] = idx_name
-            index_d['column_names'].append(col)
+            if col is not None:
+                index_d['column_names'].append(col)
             index_d['unique'] = unique
         return indexes
 
diff --git a/test/dialect/test_postgresql.py b/test/dialect/test_postgresql.py
index a15fc63df5..391f120223 100644
--- a/test/dialect/test_postgresql.py
+++ b/test/dialect/test_postgresql.py
@@ -1541,6 +1541,28 @@ class MiscTest(fixtures.TestBase, AssertsExecutionResults, AssertsCompiledSQL):
                 'expression-based index idx3'
             ])
 
+    @testing.provide_metadata
+    def test_index_reflection_modified(self):
+        """reflect indexes when a column name has changed - PG 9 
+        does not update the name of the column in the index def.
+        [ticket:2141]
+
+        """
+
+        metadata = self.metadata
+
+        t1 = Table('t', metadata,
+            Column('id', Integer, primary_key=True),
+            Column('x', Integer)
+        )
+        metadata.create_all()
+        conn = testing.db.connect().execution_options(autocommit=True)
+        conn.execute("CREATE INDEX idx1 ON t (x)")
+        conn.execute("ALTER TABLE t RENAME COLUMN x to y")
+
+        ind = testing.db.dialect.get_indexes(conn, "t", None)
+        eq_(ind, [{'unique': False, 'column_names': [u'y'], 'name': u'idx1'}])
+        conn.close()
 
     @testing.fails_on('+zxjdbc', 'psycopg2/pg8000 specific assertion')
     @testing.fails_on('pypostgresql',
-- 
2.39.5