Run bracket interpretation for reflection

Fixed bug where a schema name given with brackets, but no dots inside the
name, for parameters such as :paramref:`_schema.Table.schema` would not be
interpreted within the context of the SQL Server dialect's documented
behavior of interpreting explicit brackets as token delimiters, first added
in 1.2 for #2626, when referring to the schema name in reflection
operations. The original assumption for #2626's behavior was that the
special interpretation of brackets was only significant if dots were
present, however in practice, the brackets are not included as part of the
identifier name for all SQL rendering operations since these are not valid
characters within regular or delimited identifiers.  Pull request courtesy
Shan.

Fixes: #9133
Closes: #9134
Pull-request: https://github.com/sqlalchemy/sqlalchemy/pull/9134
Pull-request-sha: 5dac87c82cd3063dd8e50f0075c7c00330be6439

Change-Id: I7a507bc38d75a04ffcb7e920298775baae22c6d1

diff --git a/doc/build/changelog/unreleased_14/9133.rst b/doc/build/changelog/unreleased_14/9133.rst
new file mode 100644 (file)
index 0000000..29e05f5
--- /dev/null
+++ b/doc/build/changelog/unreleased_14/9133.rst
@@ -0,0 +1,16 @@
+.. change::
+    :tags: bug, mssql
+    :tickets: 9133
+
+    Fixed bug where a schema name given with brackets, but no dots inside the
+    name, for parameters such as :paramref:`_schema.Table.schema` would not be
+    interpreted within the context of the SQL Server dialect's documented
+    behavior of interpreting explicit brackets as token delimiters, first added
+    in 1.2 for #2626, when referring to the schema name in reflection
+    operations. The original assumption for #2626's behavior was that the
+    special interpretation of brackets was only significant if dots were
+    present, however in practice, the brackets are not included as part of the
+    identifier name for all SQL rendering operations since these are not valid
+    characters within regular or delimited identifiers.  Pull request courtesy
+    Shan.
+

diff --git a/lib/sqlalchemy/dialects/mssql/base.py b/lib/sqlalchemy/dialects/mssql/base.py
index b1f30d577248441caf2bb8c488951dd6a75fdb76..eabea88db64e45043ea7efeff2b2f7a2d81c5ef0 100644 (file)
--- a/lib/sqlalchemy/dialects/mssql/base.py
+++ b/lib/sqlalchemy/dialects/mssql/base.py
@@ -2871,10 +2871,8 @@ def _switch_db(dbname, connection, fn, *arg, **kw):
 def _owner_plus_db(dialect, schema):
     if not schema:
         return None, dialect.default_schema_name
-    elif "." in schema:
-        return _schema_elements(schema)
     else:
-        return None, schema
+        return _schema_elements(schema)
 
 
 _memoized_schema = util.LRUCache()

diff --git a/test/dialect/mssql/test_compiler.py b/test/dialect/mssql/test_compiler.py
index 00bbc2af45fd7c8c5531367f9ddc8b85b779e989..0076c76fd905e47e1b55649c2c888aed655ed91c 100644 (file)
--- a/test/dialect/mssql/test_compiler.py
+++ b/test/dialect/mssql/test_compiler.py
@@ -599,6 +599,47 @@ class CompileTest(fixtures.TestBase, AssertsCompiledSQL):
             checkpositional=("bar",),
         )
 
+    @testing.variation("use_schema_translate", [True, False])
+    @testing.combinations(
+        "abc", "has spaces", "[abc]", "[has spaces]", argnames="schemaname"
+    )
+    def test_schema_single_token_bracketed(
+        self, use_schema_translate, schemaname
+    ):
+        """test for #9133.
+
+        this is not the actual regression case for #9133, which is instead
+        within the reflection process.  However, when we implemented
+        #2626, we never considered the case of ``[schema]`` without any
+        dots in it.
+
+        """
+
+        schema_no_brackets = schemaname.strip("[]")
+
+        if " " in schemaname:
+            rendered_schema = "[%s]" % (schema_no_brackets,)
+        else:
+            rendered_schema = schema_no_brackets
+
+        metadata = MetaData()
+        tbl = Table(
+            "test",
+            metadata,
+            Column("id", Integer, primary_key=True),
+            schema=schemaname if not use_schema_translate else None,
+        )
+
+        self.assert_compile(
+            select(tbl),
+            "SELECT %(name)s.test.id FROM %(name)s.test"
+            % {"name": rendered_schema},
+            schema_translate_map={None: schemaname}
+            if use_schema_translate
+            else None,
+            render_schema_translate=True if use_schema_translate else False,
+        )
+
     def test_schema_many_tokens_one(self):
         metadata = MetaData()
         tbl = Table(

diff --git a/test/dialect/mssql/test_reflection.py b/test/dialect/mssql/test_reflection.py
index 1716d68e3945ef4febc5a0419ab2847fa3598c68..59b88c6ef39323db3f838d91528b5cee4c35167f 100644 (file)
--- a/test/dialect/mssql/test_reflection.py
+++ b/test/dialect/mssql/test_reflection.py
@@ -410,6 +410,35 @@ class ReflectionTest(fixtures.TestBase, ComparesTables, AssertsCompiledSQL):
             )
             Table(tname, MetaData(), autoload_with=conn)
 
+    @testing.combinations(
+        ("test_schema"),
+        ("[test_schema]"),
+        argnames="schema_value",
+    )
+    @testing.variation(
+        "reflection_operation", ["has_table", "reflect_table", "get_columns"]
+    )
+    def test_has_table_with_single_token_schema(
+        self, metadata, connection, schema_value, reflection_operation
+    ):
+        """test for #9133"""
+        tt = Table(
+            "test", metadata, Column("id", Integer), schema=schema_value
+        )
+        tt.create(connection)
+
+        if reflection_operation.has_table:
+            is_true(inspect(connection).has_table("test", schema=schema_value))
+        elif reflection_operation.reflect_table:
+            m2 = MetaData()
+            Table("test", m2, autoload_with=connection, schema=schema_value)
+        elif reflection_operation.get_columns:
+            is_true(
+                inspect(connection).get_columns("test", schema=schema_value)
+            )
+        else:
+            reflection_operation.fail()
+
     def test_db_qualified_items(self, metadata, connection):
         Table("foo", metadata, Column("id", Integer, primary_key=True))
         Table(