Revert automatic set of sequence start to 1

The :class:`.Sequence` construct restores itself to the DDL behavior it
had prior to the 1.4 series, where creating a :class:`.Sequence` with
no additional arguments will emit a simple ``CREATE SEQUENCE`` instruction
**without** any additional parameters for "start value".   For most backends,
this is how things worked previously in any case; **however**, for
MS SQL Server, the default value on this database is
``-2**63``; to prevent this generally impractical default
from taking effect on SQL Server, the :paramref:`.Sequence.start` parameter
should be provided.   As usage of :class:`.Sequence` is unusual
for SQL Server which for many years has standardized on ``IDENTITY``,
it is hoped that this change has minimal impact.

Fixes: #7211
Change-Id: I1207ea10c8cb1528a1519a0fb3581d9621c27b31

1 files changed, 30 insertions, 5 deletions

diff --git a/test/sql/test_insert.py b/test/sql/test_insert.py
index 23a850f08..395fe16d3 100644
--- a/test/sql/test_insert.py
+++ b/test/sql/test_insert.py
@@ -26,10 +26,12 @@ from sqlalchemy.sql import crud
 from sqlalchemy.testing import assert_raises
 from sqlalchemy.testing import assert_raises_message
 from sqlalchemy.testing import AssertsCompiledSQL
+from sqlalchemy.testing import config
 from sqlalchemy.testing import eq_
 from sqlalchemy.testing import expect_raises_message
 from sqlalchemy.testing import expect_warnings
 from sqlalchemy.testing import fixtures
+from sqlalchemy.testing.provision import normalize_sequence
 
 
 class ORMExpr:
@@ -143,7 +145,13 @@ class InsertTest(_InsertTestBase, fixtures.TablesTest, AssertsCompiledSQL):
         )
 
     def test_insert_literal_binds_sequence_notimplemented(self):
-        table = Table("x", MetaData(), Column("y", Integer, Sequence("y_seq")))
+        table = Table(
+            "x",
+            MetaData(),
+            Column(
+                "y", Integer, normalize_sequence(config, Sequence("y_seq"))
+            ),
+        )
         dialect = default.DefaultDialect()
         dialect.supports_sequences = True
 
@@ -407,7 +415,12 @@ class InsertTest(_InsertTestBase, fixtures.TablesTest, AssertsCompiledSQL):
         t1 = Table(
             "t",
             m,
-            Column("id", Integer, Sequence("id_seq"), primary_key=True),
+            Column(
+                "id",
+                Integer,
+                normalize_sequence(config, Sequence("id_seq")),
+                primary_key=True,
+            ),
             Column("data", String),
         )
 
@@ -428,7 +441,12 @@ class InsertTest(_InsertTestBase, fixtures.TablesTest, AssertsCompiledSQL):
         t1 = Table(
             "t",
             m,
-            Column("id", Integer, Sequence("id_seq"), primary_key=True),
+            Column(
+                "id",
+                Integer,
+                normalize_sequence(config, Sequence("id_seq")),
+                primary_key=True,
+            ),
             Column("data", String),
         )
 
@@ -453,7 +471,9 @@ class InsertTest(_InsertTestBase, fixtures.TablesTest, AssertsCompiledSQL):
             "t",
             m,
             Column("id", Integer, primary_key=True),
-            Column("counter", Sequence("counter_seq")),
+            Column(
+                "counter", normalize_sequence(config, Sequence("counter_seq"))
+            ),
             Column("data", String),
         )
 
@@ -534,7 +554,12 @@ class InsertTest(_InsertTestBase, fixtures.TablesTest, AssertsCompiledSQL):
         t1 = Table(
             "t",
             m,
-            Column("id", Integer, Sequence("id_seq"), primary_key=True),
+            Column(
+                "id",
+                Integer,
+                normalize_sequence(config, Sequence("id_seq")),
+                primary_key=True,
+            ),
             Column("data", String),
         )