FIX: Schema flushing and model schemas by benclark158 · Pull Request #497 · microsoft/mssql-django

benclark158 · 2026-02-09T17:44:03Z

Changes

Added support for models that use Meta.db_table = [schema].[table_name]
Added support for flush command to work as expected for models with non default schemas
Made schemas created as part of create table migrations.

I have added tests for tables with different defined migrations as well as flushing

Fixes: #496

benclark158 · 2026-02-09T17:45:05Z

@microsoft-github-policy-service agree

bewithgaurav · 2026-02-10T14:02:28Z

/azp run

azure-pipelines · 2026-02-10T14:02:39Z

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bewithgaurav · 2026-02-11T10:58:19Z

/azp run

azure-pipelines · 2026-02-11T10:58:29Z

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bewithgaurav · 2026-03-05T10:06:22Z

/azp run

azure-pipelines · 2026-03-05T10:06:32Z

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benclark158 · 2026-03-27T11:14:35Z

/azp run

azure-pipelines · 2026-03-27T11:14:41Z

Commenter does not have sufficient privileges for PR 497 in repo microsoft/mssql-django

bewithgaurav · 2026-03-30T06:46:31Z

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azure-pipelines · 2026-03-30T06:46:40Z

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bewithgaurav · 2026-03-31T04:20:50Z

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azure-pipelines · 2026-03-31T04:20:59Z

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Copilot

Pull request overview

This PR extends the mssql-django backend’s support for non-default SQL Server schemas, aiming to ensure models using schema-qualified db_table names behave correctly in migrations, flushing, and introspection.

Changes:

Add schema-aware FK constraint disabling/enabling during flush.
Add schema-qualified table handling in introspection (table listing and per-table queries).
Create missing schemas automatically during CREATE TABLE migrations, plus add test coverage/models/migrations for non-dbo schemas.

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 5 comments.

Show a summary per file

File	Description
`mssql/schema.py`	Adds auto-creation of schemas during `create_model()` and introduces `sql_create_schema`.
`mssql/operations.py`	Updates `sql_flush()` to include `TABLE_SCHEMA` so constraints are altered with schema-qualified table names.
`mssql/introspection.py`	Updates introspection to return schema-qualified table names and to handle schema-qualified inputs for several introspection methods.
`testapp/models.py`	Adds test models with `db_table` set to `[events].[...]` and `[dbo].[...]`.
`testapp/migrations/0026_parentschema_childschema.py`	Creates `ParentSchema`/`ChildSchema` tables in the `[events]` schema.
`testapp/migrations/0027_create_dboschema.py`	Creates `DboSchema` table in the `[dbo]` schema.
`testapp/tests/test_schema.py`	Adds tests intended to validate flushing and introspection with non-default schemas.

        # map pyodbc's cursor.columns to db-api cursor description
+        _schema_name, table_name = get_table_name_with_schema(table_name=table_name)
        columns = [[c[3], c[4], c[6], c[6], c[6], c[8], c[10], c[12]] for c in cursor.columns(table=table_name)]



                        TABLE_TYPE,
                        CAST(ep.value AS VARCHAR) AS COMMENT
                    FROM INFORMATION_SCHEMA.TABLES i
                    LEFT JOIN sys.tables t ON t.name = i.TABLE_NAME


+    sql_create_schema = (
+        "IF NOT EXISTS (SELECT 1 FROM sys.schemas WHERE name = '%(schema)s') BEGIN "
+        "EXEC('CREATE SCHEMA [%(schema)s]') "
+        "END"
+    )


+
+            sql = self.sql_create_schema % {
+                'schema': schema_name.strip('[').strip(']')
+            }
+
+            self.execute(sql, None)
+


+    def test_inspectdb(self):
+        connection = connections['default']
+
+        descs = connection.introspection.get_table_description(cursor=connection.cursor(), table_name='[events].[ParentSchema]')


saurabh500 · 2026-05-02T17:56:48Z

          constraints.insert(0, composite_pk_sql)
+
+        # Make the table schema
+        if '.' in model._meta.db_table:


. detection can be very error prone and confusing. There are a lot of edge cases that need to be considered. Table names can have . in them.

Our drivers for mssql server have a multi part identifier parsing. Once instance is https://github.com/microsoft/mssql-rs/blob/e374c4a743af9a45dfee29762afaeddaee96408b/mssql-tds/src/sql_identifier.rs#L46

We need to use a statemachine based parser instead of . detection to get this right.

saurabh500 · 2026-05-02T18:11:34Z

+            schema_name, _ = model._meta.db_table.split('.', 1)
+
+            sql = self.sql_create_schema % {
+                'schema': schema_name.strip('[').strip(']')


Sql schema names can have ] in them too.

CREATE SCHEMA [odd]]schema]

This code can incorrectly strip out wrong information

saurabh500 · 2026-05-02T22:23:43Z

+    # is supported
+
+
+    if '[' in table_name and ']' in table_name and '.' in table_name:


This requires a multi part parser. [ ] and . are valid characters of tablename

saurabh500 · 2026-05-02T22:50:42Z

        types = {'BASE TABLE': 't', 'VIEW': 'v'}
        if VERSION >= (4, 2) and self.connection.features.supports_comments:
-            return [TableInfo(row[0], types.get(row[1]), row[2])
+            return [TableInfo(f'[{row[0]}].[{row[1]}]' if row[0] != 'dbo' else row[1], types.get(row[2]), row[3])


Why this condition?

if row[0] != 'dbo'

bewithgaurav · 2026-05-22T14:27:22Z

/azp run

azure-pipelines · 2026-05-22T14:27:32Z

Azure Pipelines successfully started running 1 pipeline(s).

bewithgaurav · 2026-05-22T14:28:20Z

@benclark158 - thanks for your contribution!
gentle reminder to please address the review comments
have run the CI checks again with the new dev branch pulled in
will re-review once done.

Ben Clark added 9 commits February 9, 2026 13:03

Created failing tests

abc00b4

Adding support for models with different schemas

2775354

Added ability to create schemas without migrations

7391830

Improving handling of schemas through all queries

28f7d2b

Removing flush prints

8466e0c

Improved schema creation

34b219d

Removing settings changes

5132cff

Removed redundant changes

a8c3520

Removing unneeded changes

d793d19

Removing types for python 3.8

5bc7697

Ben Clark and others added 3 commits March 4, 2026 12:59

Fixing an issue to modules using db_table='[dbo].[table]' format

6cf5e95

Merge branch 'microsoft:dev' into schema_flushing

45110aa

Merge branch 'dev' into schema_flushing

46b41c3

benclark158 and others added 2 commits March 27, 2026 11:00

Merge branch 'dev' into schema_flushing

821e6e8

Fixing test and 3.7 incompatible code

40fbe7b

Checking name is not none

903c831

Fixing how . paths are handled without []

d616c3d

Merge branch 'dev' into schema_flushing

fc7f96d

Copilot AI review requested due to automatic review settings May 2, 2026 15:20

Copilot started reviewing on behalf of saurabh500 May 2, 2026 15:21 View session

Copilot AI reviewed May 2, 2026

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saurabh500 reviewed May 2, 2026

View reviewed changes

Merge branch 'dev' into schema_flushing

88e517f

		# is supported


		if '[' in table_name and ']' in table_name and '.' in table_name:

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