1.38.0

Case / When

Added the Case and When functions, which are the SQL equivalent of an if / elif / else block:

>>> from piccolo.query.functions import Case, When

>>> await Band.select(
...     Band.name,
...     Case(
...         When(Band.popularity > 900, then='super popular'),
...         When(Band.popularity > 500, then='popular'),
...         default='not popular',
...         alias='popularity_label',
...     ),
... )
[
    {'name': 'Pythonistas', 'popularity_label': 'super popular'},
    {'name': 'Rustaceans', 'popularity_label': 'not popular'},
    {'name': 'C-Sharps', 'popularity_label': 'popular'}
]

Thanks to @regiscamimura for adding this.

Other changes

• Auto migrations now support changing the base column type of an Array column (thanks to @sinisaos for this).
• Fixed a bug with auto migrations when adding or dropping a column which uses db_column_name (thanks to @atkei for this).
• Fixed a bug with auto migrations, where renaming a table didn't update the ForeignKey columns which reference it (thanks to @regiscamimura for this).
• Subclasses of Piccolo's Default classes can now be used as column defaults (thanks to @Bobronium for this).
• Fixed typos in the docs.