migrate - SQLAlchemy Migrate (schema change management)

Author:

Evan Rosson

Maintainer:

Domen Kožar <domenNO@SPAMdev.si>

Maintainer:

Jan Dittberner <jan.dittbernerNO@SPAMgooglemail.com>

Source Code:

https://github.com/stackforge/sqlalchemy-migrate

Documentation:

https://sqlalchemy-migrate.readthedocs.org/

Issues:

https://bugs.launchpad.net/sqlalchemy-migrate

Generated:

June 29, 2023

License:

MIT

Version:

0.7.3.dev

Overview

Inspired by Ruby on Rails’ migrations, SQLAlchemy Migrate provides a way to deal with database schema changes in SQLAlchemy projects.

Migrate was started as part of Google’s Summer of Code by Evan Rosson, mentored by Jonathan LaCour.

The project was taken over by a small group of volunteers when Evan had no free time for the project. It is now hosted as a Github project. During the hosting change the project was renamed to SQLAlchemy Migrate.

Currently, sqlalchemy-migrate supports Python versions from 2.6 to 2.7. SQLAlchemy Migrate 0.7.2 supports SQLAlchemy 0.6.x and 0.7.x branches.

Support for Python 2.4 and 2.5 as well as SQLAlchemy 0.5.x has been dropped after sqlalchemy-migrate 0.7.1.

Warning

Version 0.6 broke backward compatibility, please read changelog for more info.

Download and Development

• Download
• Development
• Credits

Dialect support

Operation / Dialect	sqlite	postgres	mysql	oracle	firebird	mssql	DB2
ALTER TABLE RENAME TABLE	yes	yes	yes	yes	no	not supported	unknown
ALTER TABLE RENAME COLUMN	yes (workaround) [5]	yes	yes	yes	yes	not supported	unknown
ALTER TABLE ADD COLUMN	yes (workaround) [6]	yes	yes	yes	yes	not supported	unknown
ALTER TABLE DROP COLUMN	yes (workaround) [5]	yes	yes	yes	yes	not supported	unknown
ALTER TABLE ALTER COLUMN	yes (workaround) [5]	yes	yes	yes (with limitations) [7]	yes [8]	not supported	unknown
ALTER TABLE ADD CONSTRAINT	partial (workaround) [5]	yes	yes	yes	yes	not supported	unknown
ALTER TABLE DROP CONSTRAINT	partial (workaround) [5]	yes	yes	yes	yes	not supported	unknown
RENAME INDEX	no	yes	no	yes	yes	not supported	unknown

[5] (1,2,3,4,5)

Table is renamed to temporary table, new table is created followed by INSERT statements.

[6]

See http://www.sqlite.org/lang_altertable.html for more information. In cases not supported by sqlite, table is renamed to temporary table, new table is created followed by INSERT statements.

[7]

You can not change datatype or rename column if table has NOT NULL data, see http://blogs.x2line.com/al/archive/2005/08/30/1231.aspx for more information.

[8]

Changing nullable is not supported

Tutorials

List of useful tutorials:

• Using migrate with Elixir

• Developing with migrations

User guide

SQLAlchemy Migrate is split into two parts, database schema versioning (migrate.versioning) and database migration management (migrate.changeset). The versioning API is available as the migrate command.

• Database schema versioning workflow
  • Project setup
    • Create a change repository
    • Version control a database
    • Project management script
  • Making schema changes
    • Create a change script
    • Edit the change script
    • Test the change script
    • Upgrade the database
    • Modifying existing tables
  • Writing change scripts
    • Writing scripts with consistent behavior
    • Writing for a specific database
    • Writings .sql scripts
  • Command line usage
  • Python API
  • Experimental commands
  • Repository configuration
  • Customize templates
• Database schema migrations
  • Column
  • Table
  • Index
  • Constraint
    • Examples
• Repository migration (0.4.5 -> 0.5.4)
• FAQ
  • Q: Adding a nullable=False column
• Glossary

API Documentation

• Module migrate.changeset – Schema changes
  • Module migrate.changeset – Schema migration API
  • Module ansisql – Standard SQL implementation
    • ANSIColumnDropper
      • ANSIColumnDropper.visit_column()
    • ANSIColumnGenerator
      • ANSIColumnGenerator.visit_column()
    • ANSIConstraintCommon
      • ANSIConstraintCommon.get_constraint_name()
    • ANSIConstraintDropper
    • ANSIConstraintGenerator
    • ANSIDialect
      • ANSIDialect.columndropper
      • ANSIDialect.columngenerator
      • ANSIDialect.constraintdropper
      • ANSIDialect.constraintgenerator
      • ANSIDialect.schemachanger
    • ANSISchemaChanger
      • ANSISchemaChanger.start_alter_column()
      • ANSISchemaChanger.visit_column()
      • ANSISchemaChanger.visit_index()
      • ANSISchemaChanger.visit_table()
    • AlterTableVisitor
      • AlterTableVisitor.append()
      • AlterTableVisitor.execute()
      • AlterTableVisitor.start_alter_table()
  • Module constraint – Constraint schema migration API
    • CheckConstraint
      • CheckConstraint.argument_for()
      • CheckConstraint.contains_column()
      • CheckConstraint.copy()
      • CheckConstraint.create()
      • CheckConstraint.drop()
      • CheckConstraint.get_children()
      • CheckConstraint.columns
      • CheckConstraint.dialect_kwargs
      • CheckConstraint.dialect_options
      • CheckConstraint.info
      • CheckConstraint.kwargs
    • ConstraintChangeset
      • ConstraintChangeset.create()
      • ConstraintChangeset.drop()
    • ForeignKeyConstraint
      • ForeignKeyConstraint.argument_for()
      • ForeignKeyConstraint.autoname()
      • ForeignKeyConstraint.contains_column()
      • ForeignKeyConstraint.copy()
      • ForeignKeyConstraint.create()
      • ForeignKeyConstraint.drop()
      • ForeignKeyConstraint.get_children()
      • ForeignKeyConstraint.column_keys
      • ForeignKeyConstraint.columns
      • ForeignKeyConstraint.dialect_kwargs
      • ForeignKeyConstraint.dialect_options
      • ForeignKeyConstraint.elements
      • ForeignKeyConstraint.info
      • ForeignKeyConstraint.kwargs
      • ForeignKeyConstraint.referred_table
    • PrimaryKeyConstraint
      • PrimaryKeyConstraint.argument_for()
      • PrimaryKeyConstraint.autoname()
      • PrimaryKeyConstraint.contains_column()
      • PrimaryKeyConstraint.copy()
      • PrimaryKeyConstraint.create()
      • PrimaryKeyConstraint.drop()
      • PrimaryKeyConstraint.get_children()
      • PrimaryKeyConstraint.columns
      • PrimaryKeyConstraint.dialect_kwargs
      • PrimaryKeyConstraint.dialect_options
      • PrimaryKeyConstraint.info
      • PrimaryKeyConstraint.kwargs
    • UniqueConstraint
      • UniqueConstraint.argument_for()
      • UniqueConstraint.autoname()
      • UniqueConstraint.contains_column()
      • UniqueConstraint.copy()
      • UniqueConstraint.create()
      • UniqueConstraint.drop()
      • UniqueConstraint.get_children()
      • UniqueConstraint.columns
      • UniqueConstraint.dialect_kwargs
      • UniqueConstraint.dialect_options
      • UniqueConstraint.info
      • UniqueConstraint.kwargs
  • Module databases – Database specific schema migration
    • Module mysql
      • MySQLColumnDropper
      • MySQLColumnGenerator
      • MySQLConstraintDropper
      • MySQLConstraintGenerator
      • MySQLDialect
        • MySQLDialect.columndropper
        • MySQLDialect.columngenerator
        • MySQLDialect.constraintdropper
        • MySQLDialect.constraintgenerator
        • MySQLDialect.schemachanger
      • MySQLSchemaChanger
        • MySQLSchemaChanger.visit_column()
        • MySQLSchemaChanger.visit_index()
    • Module firebird
      • FBColumnDropper
        • FBColumnDropper.visit_column()
      • FBColumnGenerator
      • FBConstraintDropper
        • FBConstraintDropper.cascade_constraint()
      • FBConstraintGenerator
      • FBDialect
        • FBDialect.columndropper
        • FBDialect.columngenerator
        • FBDialect.constraintdropper
        • FBDialect.constraintgenerator
        • FBDialect.schemachanger
      • FBSchemaChanger
        • FBSchemaChanger.visit_table()
    • Module oracle
      • OracleColumnDropper
      • OracleColumnGenerator
      • OracleConstraintDropper
      • OracleConstraintGenerator
      • OracleDialect
        • OracleDialect.columndropper
        • OracleDialect.columngenerator
        • OracleDialect.constraintdropper
        • OracleDialect.constraintgenerator
        • OracleDialect.schemachanger
      • OracleSchemaChanger
        • OracleSchemaChanger.visit_column()
    • Module postgres
      • PGColumnDropper
      • PGColumnGenerator
      • PGConstraintDropper
      • PGConstraintGenerator
      • PGDialect
        • PGDialect.columndropper
        • PGDialect.columngenerator
        • PGDialect.constraintdropper
        • PGDialect.constraintgenerator
        • PGDialect.schemachanger
      • PGSchemaChanger
    • Module sqlite
      • SQLiteColumnDropper
        • SQLiteColumnDropper.visit_column()
      • SQLiteColumnGenerator
        • SQLiteColumnGenerator.visit_column()
      • SQLiteConstraintDropper
      • SQLiteConstraintGenerator
      • SQLiteDialect
        • SQLiteDialect.columndropper
        • SQLiteDialect.columngenerator
        • SQLiteDialect.constraintdropper
        • SQLiteDialect.constraintgenerator
        • SQLiteDialect.schemachanger
      • SQLiteSchemaChanger
        • SQLiteSchemaChanger.visit_index()
    • Module visitor
      • get_dialect_visitor()
      • get_engine_visitor()
      • run_single_visitor()
  • Module schema – Additional API to SQLAlchemy for migrations
    • ChangesetColumn
      • ChangesetColumn.alter()
      • ChangesetColumn.copy_fixed()
      • ChangesetColumn.create()
      • ChangesetColumn.drop()
    • ChangesetDefaultClause
    • ChangesetIndex
      • ChangesetIndex.rename()
    • ChangesetTable
      • ChangesetTable.create_column()
      • ChangesetTable.deregister()
      • ChangesetTable.drop_column()
      • ChangesetTable.rename()
    • ColumnDelta
      • ColumnDelta.apply_diffs()
      • ColumnDelta.are_column_types_eq()
      • ColumnDelta.compare_1_column()
      • ColumnDelta.compare_2_columns()
      • ColumnDelta.compare_parameters()
      • ColumnDelta.keys()
      • ColumnDelta.process_column()
    • alter_column()
    • create_column()
    • drop_column()
    • rename_index()
    • rename_table()
• Module migrate.versioning – Database versioning and repository management
  • Module api – Python API commands
    • compare_model_to_db()
    • create()
    • create_model()
    • db_version()
    • downgrade()
    • drop_version_control()
    • help()
    • make_update_script_for_model()
    • manage()
    • script()
    • script_sql()
    • source()
    • test()
    • update_db_from_model()
    • upgrade()
    • version()
    • version_control()
  • Module genmodel – ORM Model generator
    • ModelGenerator
      • ModelGenerator.genB2AMigration()
      • ModelGenerator.genBDefinition()
      • ModelGenerator.runB2A()
  • Module pathed – Path utilities
    • Pathed
      • Pathed.require_found()
      • Pathed.require_notfound()
  • Module repository – Repository management
    • Changeset
      • Changeset.add()
      • Changeset.items()
      • Changeset.keys()
      • Changeset.run()
      • Changeset.values()
    • Repository
      • Repository.changeset()
      • Repository.create()
      • Repository.create_manage_file()
      • Repository.create_script()
      • Repository.create_script_sql()
      • Repository.prepare_config()
      • Repository.verify()
      • Repository.version()
      • Repository.id
      • Repository.latest
      • Repository.use_timestamp_numbering
      • Repository.version_table
  • Module schema – Migration upgrade/downgrade
    • ControlledSchema
      • ControlledSchema.changeset()
      • ControlledSchema.compare_model_to_db()
      • ControlledSchema.create()
      • ControlledSchema.create_model()
      • ControlledSchema.drop()
      • ControlledSchema.load()
      • ControlledSchema.update_db_from_model()
      • ControlledSchema.update_repository_table()
      • ControlledSchema.upgrade()
  • Module schemadiff – ORM Model differencing
    • ColDiff
      • ColDiff.col_A
      • ColDiff.col_B
      • ColDiff.type_A
      • ColDiff.type_B
    • SchemaDiff
      • SchemaDiff.tables_missing_from_A
      • SchemaDiff.tables_missing_from_B
      • SchemaDiff.tables_different
    • TableDiff
      • TableDiff.columns_missing_from_A
      • TableDiff.columns_missing_from_B
      • TableDiff.columns_different
    • getDiffOfModelAgainstDatabase()
    • getDiffOfModelAgainstModel()
  • Module script – Script actions
    • BaseScript
      • BaseScript.run()
      • BaseScript.source()
      • BaseScript.verify()
    • PythonScript
      • PythonScript.create()
      • PythonScript.make_update_script_for_model()
      • PythonScript.preview_sql()
      • PythonScript.require_found()
      • PythonScript.require_notfound()
      • PythonScript.run()
      • PythonScript.source()
      • PythonScript.verify()
      • PythonScript.verify_module()
      • PythonScript.module
    • SqlScript
      • SqlScript.create()
      • SqlScript.require_found()
      • SqlScript.require_notfound()
      • SqlScript.run()
      • SqlScript.source()
      • SqlScript.verify()
  • Module shell – CLI interface
    • PassiveOptionParser
    • main()
  • Module util – Various utility functions
    • Memoize
    • asbool()
    • construct_engine()
    • guess_obj_type()
    • load_model()
  • Module version – Versioning management
    • Collection
      • Collection.create_new_python_version()
      • Collection.create_new_sql_version()
      • Collection.version()
      • Collection.latest
    • Extensions
    • VerNum
    • Version
      • Version.add_script()
      • Version.script()
    • str_to_filename()
• Module exceptions – Exception definitions
  • ApiError
  • ControlledSchemaError
  • DatabaseAlreadyControlledError
  • DatabaseNotControlledError
  • Error
  • InvalidConstraintError
  • InvalidRepositoryError
  • InvalidScriptError
  • InvalidVersionError
  • KnownError
  • MigrateDeprecationWarning
  • NoSuchTableError
  • NotSupportedError
  • PathError
  • PathFoundError
  • PathNotFoundError
  • RepositoryError
  • ScriptError
  • UsageError
  • VersionNotFoundError
  • WrongRepositoryError

Changelog

• 0.7.3 (201x-xx-xx)
  • Changes
  • Documentation
  • Features
  • Fixed Bugs
• 0.7.2 (2011-11-01)
  • Changes
  • Documentation
  • Features
  • Fixed Bugs
• 0.7.1 (2011-05-27)
  • Fixed Bugs
• 0.7 (2011-05-27)
  • Features
  • Fixed bugs
• 0.6.1 (2011-02-11)
  • Features
  • Fixed bugs
• 0.6 (11.07.2010)
  • Features
  • Fixed bugs
  • Documentation
• 0.5.4
• 0.5.3
• 0.5.2
• 0.5.1.2
• 0.5.1.1
• 0.5.1
• 0.4.5
• 0.4.4
• 0.4.3
• 0.4.2
• 0.4.1
• 0.4.0
• 0.3
• 0.2.3
• 0.2.2
• 0.2.1

Indices and tables

• Index

• Module Index

• Search Page