def _alter_field(self, model, old_field, new_field, old_type, new_type,
old_db_params, new_db_params, strict=False):
# ALTER COLUMN TYPE is experimental.
# https://github.com/cockroachdb/cockroach/issues/49329
if (self.connection.features.is_cockroachdb_21_1 and old_type != new_type or
getattr(old_field, 'db_collation', None) != getattr(new_field, 'db_collation', None)):
self.execute('SET enable_experimental_alter_column_type_general = true')
# Skip to the base class to avoid trying to add or drop
# PostgreSQL-specific LIKE indexes.
BaseDatabaseSchemaEditor._alter_field(
self, model, old_field, new_field, old_type, new_type, old_db_params,
new_db_params, strict,
)
# Add or remove `DEFAULT unique_rowid()` for AutoField.
old_suffix = old_field.db_type_suffix(self.connection)
new_suffix = new_field.db_type_suffix(self.connection)
if old_suffix != new_suffix:
if new_suffix:
self.execute(self.sql_alter_column % {
'table': self.quote_name(model._meta.db_table),
'changes': 'ALTER COLUMN %(column)s SET %(expression)s' % {
'column': self.quote_name(new_field.column),
'expression': new_suffix,
}
})
else:
self.execute(self.sql_alter_column % {
'table': self.quote_name(model._meta.db_table),
'changes': 'ALTER COLUMN %(column)s DROP DEFAULT' % {
'column': self.quote_name(new_field.column),
}
})
def _alter_field(self, model, old_field, new_field, old_type, new_type,
old_db_params, new_db_params, strict=False):
# Skip to the base class to avoid trying to add or drop
# PostgreSQL-specific LIKE indexes.
BaseDatabaseSchemaEditor._alter_field(
self, model, old_field, new_field, old_type, new_type, old_db_params,
new_db_params, strict,
)
# Add or remove `DEFAULT unique_rowid()` for AutoField.
old_suffix = old_field.db_type_suffix(self.connection)
new_suffix = new_field.db_type_suffix(self.connection)
if old_suffix != new_suffix:
if new_suffix:
self.execute(self.sql_alter_column % {
'table': self.quote_name(model._meta.db_table),
'changes': 'ALTER COLUMN %(column)s SET %(expression)s' % {
'column': self.quote_name(new_field.column),
'expression': new_suffix,
}
})
else:
self.execute(self.sql_alter_column % {
'table': self.quote_name(model._meta.db_table),
'changes': 'ALTER COLUMN %(column)s DROP DEFAULT' % {
'column': self.quote_name(new_field.column),
}
})
def _alter_field(self, model, old_field, new_field, old_type, new_type,
old_db_params, new_db_params, strict=False):
# Skip to the base class to avoid trying to add or drop
# PostgreSQL-specific LIKE indexes.
BaseDatabaseSchemaEditor._alter_field(
self, model, old_field, new_field, old_type, new_type, old_db_params,
new_db_params, strict,
)
def _alter_field(self, model, old_field, new_field, old_type, new_type,
old_db_params, new_db_params, strict=False):
if old_field.db_index or old_field.unique:
index_name = self._create_index_name(model._meta.db_table, [old_field.column])
self.execute(self._delete_index_sql(model, index_name))
BaseDatabaseSchemaEditor._alter_field(
self, model, old_field, new_field, old_type, new_type, old_db_params,
new_db_params, strict,
)
