Call nextval() on sequence when doing INSERT from SELECT

Fixed bug where an INSERT from SELECT where the source table contains
an autoincrementing Sequence would fail to compile correctly.

Change-Id: I41eb9f65789a4007712ae61ed5fa23a9839a5128
Fixes: #3877

1 files changed, 20 insertions, 1 deletions

diff --git a/test/sql/test_insert.py b/test/sql/test_insert.py
index 2fa1860de..73731e952 100644
--- a/test/sql/test_insert.py
+++ b/test/sql/test_insert.py
@@ -1,7 +1,8 @@
 #! coding:utf-8
 
 from sqlalchemy import Column, Integer, MetaData, String, Table,\
-    bindparam, exc, func, insert, select, column, text, table
+    bindparam, exc, func, insert, select, column, text, table,\
+    Sequence
 from sqlalchemy.dialects import mysql, postgresql
 from sqlalchemy.engine import default
 from sqlalchemy.testing import AssertsCompiledSQL,\
@@ -238,6 +239,24 @@ class InsertTest(_InsertTestBase, fixtures.TablesTest, AssertsCompiledSQL):
             checkparams={"name_1": "foo"}
         )
 
+    def test_insert_from_select_seq(self):
+        m = MetaData()
+
+        t1 = Table(
+            't', m,
+            Column('id', Integer, Sequence('id_seq'), primary_key=True),
+            Column('data', String)
+        )
+
+        stmt = t1.insert().from_select(('data', ), select([t1.c.data]))
+
+        self.assert_compile(
+            stmt,
+            "INSERT INTO t (data, id) SELECT t.data, "
+            "nextval('id_seq') AS next_value_1 FROM t",
+            dialect=postgresql.dialect()
+        )
+
     def test_insert_from_select_cte_one(self):
         table1 = self.tables.mytable