def sequence_reset_sql(self, style, model_list):
from django.db import models
output = []
query = self._sequence_reset_sql
for model in model_list:
for f in model._meta.local_fields:
if isinstance(f, models.AutoField):
no_autofield_sequence_name = self._get_no_autofield_sequence_name(model._meta.db_table)
table = self.quote_name(model._meta.db_table)
column = self.quote_name(f.column)
output.append(query % {
'no_autofield_sequence_name': no_autofield_sequence_name,
'table': table,
'column': column,
'table_name': strip_quotes(table),
'column_name': strip_quotes(column),
})
# Only one AutoField is allowed per model, so don't
# continue to loop
break
for f in model._meta.many_to_many:
if not f.remote_field.through:
no_autofield_sequence_name = self._get_no_autofield_sequence_name(f.m2m_db_table())
table = self.quote_name(f.m2m_db_table())
column = self.quote_name('id')
output.append(query % {
'no_autofield_sequence_name': no_autofield_sequence_name,
'table': table,
'column': column,
'table_name': strip_quotes(table),
'column_name': 'ID',
})
return output
def sequence_reset_by_name_sql(self, style, sequences):
sql = []
for sequence_info in sequences:
no_autofield_sequence_name = self._get_no_autofield_sequence_name(sequence_info['table'])
table = self.quote_name(sequence_info['table'])
column = self.quote_name(sequence_info['column'] or 'id')
query = self._sequence_reset_sql % {
'no_autofield_sequence_name': no_autofield_sequence_name,
'table': table,
'column': column,
'table_name': strip_quotes(table),
'column_name': strip_quotes(column),
}
sql.append(query)
return sql
def _get_no_autofield_sequence_name(self, table):
"""
Manually created sequence name to keep backward compatibility for
AutoFields that aren't Oracle identity columns.
"""
name_length = self.max_name_length() - 3
return '%s_SQ' % truncate_name(strip_quotes(table), name_length).upper()
def _create_index_name(self, model, column_names, suffix=""):
"""
Generates a unique name for an index/unique constraint.
The name is divided into 3 parts: the table name, the column names,
and a unique digest and suffix.
"""
table_name = strip_quotes(model._meta.db_table)
hash_data = [table_name] + list(column_names)
hash_suffix_part = "%s%s" % (self._digest(*hash_data), suffix)
max_length = self.connection.ops.max_name_length() or 200
# If everything fits into max_length, use that name.
index_name = "%s_%s_%s" % (table_name, "_".join(column_names), hash_suffix_part)
if len(index_name) <= max_length:
return index_name
# Shorten a long suffix.
if len(hash_suffix_part) > max_length / 3:
hash_suffix_part = hash_suffix_part[: max_length // 3]
other_length = (max_length - len(hash_suffix_part)) // 2 - 1
index_name = "%s_%s_%s" % (table_name[:other_length], "_".join(column_names)[:other_length], hash_suffix_part)
# Prepend D if needed to prevent the name from starting with an
# underscore or a number (not permitted on Oracle).
if index_name[0] == "_" or index_name[0].isdigit():
index_name = "D%s" % index_name[:-1]
return index_name
def _alter_column_type_sql(self, model, old_field, new_field, new_type):
self.sql_alter_column_type = 'ALTER COLUMN %(column)s TYPE %(type)s'
# Cast when data type changed.
if self._field_data_type(old_field) != self._field_data_type(
new_field):
self.sql_alter_column_type += ' USING %(column)s::%(type)s'
# Make ALTER TYPE with SERIAL make sense.
table = strip_quotes(model._meta.db_table)
serial_fields_map = {
'bigserial': 'bigint',
'serial': 'integer',
'smallserial': 'smallint'
}
if new_type.lower() in serial_fields_map:
column = strip_quotes(new_field.column)
sequence_name = "%s_%s_seq" % (table, column)
return (
(
self.sql_alter_column_type % {
"column": self.quote_name(column),
"type": serial_fields_map[new_type.lower()],
},
[],
),
[
(
self.sql_delete_sequence % {
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_create_sequence % {
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_alter_column % {
"table": self.quote_name(table),
"changes": self.sql_alter_column_default % {
"column":
self.quote_name(column),
"default":
"nextval('%s')" %
self.quote_name(sequence_name),
}
},
[],
),
(
self.sql_set_sequence_max % {
"table": self.quote_name(table),
"column": self.quote_name(column),
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_set_sequence_owner % {
'table': self.quote_name(table),
'column': self.quote_name(column),
'sequence': self.quote_name(sequence_name),
},
[],
),
],
)
else:
return super()._alter_column_type_sql(model, old_field, new_field,
new_type)
def last_insert_id(self, cursor, table_name, pk_name):
sq_name = self._get_sequence_name(cursor, strip_quotes(table_name), pk_name)
cursor.execute('"%s".currval' % sq_name)
return cursor.fetchone()[0]
def _get_trigger_name(self, table):
name_length = self.max_name_length() - 3
trigger_name = '%s_TR' % strip_quotes(table)
return truncate_name(trigger_name, name_length).upper()
def _get_sequence_name(self, table):
name_length = self.max_name_length() - 3
sequence_name = '%s_SQ' % strip_quotes(table)
return truncate_name(sequence_name, name_length).upper()
def _create_spatial_index_name(self, model, field):
# Oracle doesn't allow object names > 30 characters. Use this scheme
# instead of self._create_index_name() for backwards compatibility.
return truncate_name('%s_%s_id' % (strip_quotes(model._meta.db_table), field.column), 30)
def _alter_column_type_sql(self, model, old_field, new_field, new_type):
self.sql_alter_column_type = "ALTER COLUMN %(column)s TYPE %(type)s"
# Cast when data type changed.
using_sql = " USING %(column)s::%(type)s"
new_internal_type = new_field.get_internal_type()
old_internal_type = old_field.get_internal_type()
if new_internal_type == "ArrayField" and new_internal_type == old_internal_type:
# Compare base data types for array fields.
if list(self._field_base_data_types(old_field)) != list(
self._field_base_data_types(new_field)
):
self.sql_alter_column_type += using_sql
elif self._field_data_type(old_field) != self._field_data_type(new_field):
self.sql_alter_column_type += using_sql
# Make ALTER TYPE with IDENTITY make sense.
table = strip_quotes(model._meta.db_table)
auto_field_types = {
"AutoField",
"BigAutoField",
"SmallAutoField",
}
old_is_auto = old_internal_type in auto_field_types
new_is_auto = new_internal_type in auto_field_types
if new_is_auto and not old_is_auto:
column = strip_quotes(new_field.column)
return (
(
self.sql_alter_column_type
% {
"column": self.quote_name(column),
"type": new_type,
},
[],
),
[
(
self.sql_add_identity
% {
"table": self.quote_name(table),
"column": self.quote_name(column),
},
[],
),
],
)
elif old_is_auto and not new_is_auto:
# Drop IDENTITY if exists (pre-Django 4.1 serial columns don't have
# it).
self.execute(
self.sql_drop_indentity
% {
"table": self.quote_name(table),
"column": self.quote_name(strip_quotes(old_field.column)),
}
)
column = strip_quotes(new_field.column)
sequence_name = "%s_%s_seq" % (table, column)
fragment, _ = super()._alter_column_type_sql(
model, old_field, new_field, new_type
)
return fragment, [
(
# Drop the sequence if exists (Django 4.1+ identity columns
# don't have it).
self.sql_delete_sequence
% {
"sequence": self.quote_name(sequence_name),
},
[],
),
]
else:
return super()._alter_column_type_sql(model, old_field, new_field, new_type)
def _database_exists(self, cursor, database_name):
cursor.execute('SELECT 1 FROM pg_catalog.pg_database WHERE datname = %s', [strip_quotes(database_name)])
return cursor.fetchone() is not None
def last_insert_id(self, cursor, table_name, pk_name):
sq_name = self._get_sequence_name(cursor, strip_quotes(table_name),
pk_name)
cursor.execute('"%s".currval' % sq_name)
return cursor.fetchone()[0]
def _get_trigger_name(self, table):
name_length = self.max_name_length() - 3
trigger_name = '%s_TR' % strip_quotes(table)
return truncate_name(trigger_name, name_length).upper()
def _database_exists(self, cursor, database_name):
cursor.execute('SELECT 1 FROM pg_catalog.pg_database WHERE datname = %s', [strip_quotes(database_name)])
return cursor.fetchone() is not None
def _remake_table(self, model, create_field=None, delete_field=None, alter_field=None):
"""
Shortcut to transform a model from old_model into new_model
This follows the correct procedure to perform non-rename or column
addition operations based on SQLite's documentation
https://www.sqlite.org/lang_altertable.html#caution
The essential steps are:
1. Create a table with the updated definition called "new__app_model"
2. Copy the data from the existing "app_model" table to the new table
3. Drop the "app_model" table
4. Rename the "new__app_model" table to "app_model"
5. Restore any index of the previous "app_model" table.
"""
# Self-referential fields must be recreated rather than copied from
# the old model to ensure their remote_field.field_name doesn't refer
# to an altered field.
def is_self_referential(f):
return f.is_relation and f.remote_field.model is model
# Work out the new fields dict / mapping
body = {
f.name: f.clone() if is_self_referential(f) else f
for f in model._meta.local_concrete_fields
}
# Since mapping might mix column names and default values,
# its values must be already quoted.
mapping = {f.column: self.quote_name(
f.column) for f in model._meta.local_concrete_fields}
# This maps field names (not columns) for things like unique_together
rename_mapping = {}
# If any of the new or altered fields is introducing a new PK,
# remove the old one
restore_pk_field = None
if getattr(create_field, 'primary_key', False) or (
alter_field and getattr(alter_field[1], 'primary_key', False)):
for name, field in list(body.items()):
if field.primary_key:
field.primary_key = False
restore_pk_field = field
if field.auto_created:
del body[name]
del mapping[field.column]
# Add in any created fields
if create_field:
body[create_field.name] = create_field
# Choose a default and insert it into the copy map
if not create_field.many_to_many and create_field.concrete:
mapping[create_field.column] = self.quote_value(
self.effective_default(create_field)
)
# Add in any altered fields
if alter_field:
old_field, new_field = alter_field
body.pop(old_field.name, None)
mapping.pop(old_field.column, None)
body[new_field.name] = new_field
if old_field.null and not new_field.null:
case_sql = "coalesce(%(col)s, %(default)s)" % {
'col': self.quote_name(old_field.column),
'default': self.quote_value(self.effective_default(new_field))
}
mapping[new_field.column] = case_sql
else:
mapping[new_field.column] = self.quote_name(old_field.column)
rename_mapping[old_field.name] = new_field.name
# Remove any deleted fields
if delete_field:
del body[delete_field.name]
del mapping[delete_field.column]
# Remove any implicit M2M tables
if delete_field.many_to_many and delete_field.remote_field.through._meta.auto_created:
return self.delete_model(delete_field.remote_field.through)
# Work inside a new app registry
apps = Apps()
# Work out the new value of unique_together, taking renames into
# account
unique_together = [
[rename_mapping.get(n, n) for n in unique]
for unique in model._meta.unique_together
]
# Work out the new value for index_together, taking renames into
# account
index_together = [
[rename_mapping.get(n, n) for n in index]
for index in model._meta.index_together
]
indexes = model._meta.indexes
if delete_field:
indexes = [
index for index in indexes
if delete_field.name not in index.fields
]
constraints = list(model._meta.constraints)
# Provide isolated instances of the fields to the new model body so
# that the existing model's internals aren't interfered with when
# the dummy model is constructed.
body_copy = copy.deepcopy(body)
# Construct a new model with the new fields to allow self referential
# primary key to resolve to. This model won't ever be materialized as a
# table and solely exists for foreign key reference resolution purposes.
# This wouldn't be required if the schema editor was operating on model
# states instead of rendered models.
meta_contents = {
'app_label': model._meta.app_label,
'db_table': model._meta.db_table,
'unique_together': unique_together,
'index_together': index_together,
'indexes': indexes,
'constraints': constraints,
'apps': apps,
}
meta = type("Meta", (), meta_contents)
body_copy['Meta'] = meta
body_copy['__module__'] = model.__module__
type(model._meta.object_name, model.__bases__, body_copy)
# Construct a model with a renamed table name.
body_copy = copy.deepcopy(body)
meta_contents = {
'app_label': model._meta.app_label,
'db_table': 'new__%s' % strip_quotes(model._meta.db_table),
'unique_together': unique_together,
'index_together': index_together,
'indexes': indexes,
'constraints': constraints,
'apps': apps,
}
meta = type("Meta", (), meta_contents)
body_copy['Meta'] = meta
body_copy['__module__'] = model.__module__
new_model = type('New%s' % model._meta.object_name,
model.__bases__, body_copy)
# Create a new table with the updated schema.
self.create_model(new_model)
# Copy data from the old table into the new table
self.execute("INSERT INTO %s %s SELECT %s FROM %s" % (
self.quote_name(new_model._meta.db_table),
', '.join(self.quote_name(x) for x in mapping),
', '.join(mapping.values()),
self.quote_name(model._meta.db_table),
))
# Delete the old table to make way for the new
self.delete_model(model, handle_autom2m=False)
# Rename the new table to take way for the old
self.alter_db_table(
new_model, new_model._meta.db_table, model._meta.db_table,
disable_constraints=False,
)
# Run deferred SQL on correct table
for sql in self.deferred_sql:
self.execute(sql)
self.deferred_sql = []
# Fix any PK-removed field
if restore_pk_field:
restore_pk_field.primary_key = True
def create_object_name(ops, obj, sufix=''):
name_length = ops.max_name_length() - len(sufix)
obj_name = utils.strip_quotes(obj)
return utils.truncate_name(obj_name, name_length)
def _create_spatial_index_name(self, model, field):
# Oracle doesn't allow object names > 30 characters. Use this scheme
# instead of self._create_index_name() for backwards compatibility.
return truncate_name(
"%s_%s_id" % (strip_quotes(model._meta.db_table), field.column),
30)
def _alter_column_type_sql(self, model, old_field, new_field, new_type):
self.sql_alter_column_type = "ALTER COLUMN %(column)s TYPE %(type)s"
# Cast when data type changed.
using_sql = " USING %(column)s::%(type)s"
new_internal_type = new_field.get_internal_type()
old_internal_type = old_field.get_internal_type()
if new_internal_type == "ArrayField" and new_internal_type == old_internal_type:
# Compare base data types for array fields.
if list(self._field_base_data_types(old_field)) != list(
self._field_base_data_types(new_field)):
self.sql_alter_column_type += using_sql
elif self._field_data_type(old_field) != self._field_data_type(
new_field):
self.sql_alter_column_type += using_sql
# Make ALTER TYPE with SERIAL make sense.
table = strip_quotes(model._meta.db_table)
serial_fields_map = {
"bigserial": "bigint",
"serial": "integer",
"smallserial": "smallint",
}
if new_type.lower() in serial_fields_map:
column = strip_quotes(new_field.column)
sequence_name = "%s_%s_seq" % (table, column)
return (
(
self.sql_alter_column_type % {
"column": self.quote_name(column),
"type": serial_fields_map[new_type.lower()],
},
[],
),
[
(
self.sql_delete_sequence % {
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_create_sequence % {
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_alter_column % {
"table": self.quote_name(table),
"changes": self.sql_alter_column_default % {
"column":
self.quote_name(column),
"default":
"nextval('%s')" %
self.quote_name(sequence_name),
},
},
[],
),
(
self.sql_set_sequence_max % {
"table": self.quote_name(table),
"column": self.quote_name(column),
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_set_sequence_owner % {
"table": self.quote_name(table),
"column": self.quote_name(column),
"sequence": self.quote_name(sequence_name),
},
[],
),
],
)
else:
return super()._alter_column_type_sql(model, old_field, new_field,
new_type)
def _get_sequence_name(self, table):
name_length = self.max_name_length() - 3
sequence_name = '%s_SQ' % strip_quotes(table)
return truncate_name(sequence_name, name_length).upper()
def _alter_column_type_sql(self, model, old_field, new_field, new_type):
self.sql_alter_column_type = 'ALTER COLUMN %(column)s TYPE %(type)s'
# Cast when data type changed.
using_sql = ' USING %(column)s::%(type)s'
new_internal_type = new_field.get_internal_type()
old_internal_type = old_field.get_internal_type()
if new_internal_type == 'ArrayField' and new_internal_type == old_internal_type:
# Compare base data types for array fields.
if list(self._field_base_data_types(old_field)) != list(
self._field_base_data_types(new_field)):
self.sql_alter_column_type += using_sql
elif self._field_data_type(old_field) != self._field_data_type(
new_field):
self.sql_alter_column_type += using_sql
# Make ALTER TYPE with SERIAL make sense.
table = strip_quotes(model._meta.db_table)
serial_fields_map = {
'bigserial': 'bigint',
'serial': 'integer',
'smallserial': 'smallint'
}
if new_type.lower() in serial_fields_map:
column = strip_quotes(new_field.column)
sequence_name = "%s_%s_seq" % (table, column)
return (
(
self.sql_alter_column_type % {
"column": self.quote_name(column),
"type": serial_fields_map[new_type.lower()],
},
[],
),
[
(
self.sql_delete_sequence % {
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_create_sequence % {
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_alter_column % {
"table": self.quote_name(table),
"changes": self.sql_alter_column_default % {
"column":
self.quote_name(column),
"default":
"nextval('%s')" %
self.quote_name(sequence_name),
}
},
[],
),
(
self.sql_set_sequence_max % {
"table": self.quote_name(table),
"column": self.quote_name(column),
"sequence": self.quote_name(sequence_name),
},
[],
),
(
self.sql_set_sequence_owner % {
'table': self.quote_name(table),
'column': self.quote_name(column),
'sequence': self.quote_name(sequence_name),
},
[],
),
],
)
elif old_field.db_parameters(
connection=self.connection)['type'] in serial_fields_map:
# Drop the sequence if migrating away from AutoField.
column = strip_quotes(new_field.column)
sequence_name = '%s_%s_seq' % (table, column)
fragment, _ = super()._alter_column_type_sql(
model, old_field, new_field, new_type)
return fragment, [
(
self.sql_delete_sequence % {
'sequence': self.quote_name(sequence_name),
},
[],
),
]
else:
return super()._alter_column_type_sql(model, old_field, new_field,
new_type)
