django1/django/core/management/sql.py

492 lines
22 KiB
Python

from django.core.management.base import CommandError
import os
import re
try:
set
except NameError:
from sets import Set as set # Python 2.3 fallback
def table_list():
"Returns a list of all table names that exist in the database."
from django.db import connection, get_introspection_module
cursor = connection.cursor()
return get_introspection_module().get_table_list(cursor)
def django_table_list(only_existing=False):
"""
Returns a list of all table names that have associated Django models and
are in INSTALLED_APPS.
If only_existing is True, the resulting list will only include the tables
that actually exist in the database.
"""
from django.db import models
tables = []
for app in models.get_apps():
for model in models.get_models(app):
tables.append(model._meta.db_table)
tables.extend([f.m2m_db_table() for f in model._meta.many_to_many])
if only_existing:
existing = table_list()
tables = [t for t in tables if t in existing]
return tables
def installed_models(table_list):
"Returns a set of all models that are installed, given a list of existing table names."
from django.db import connection, models
all_models = []
for app in models.get_apps():
for model in models.get_models(app):
all_models.append(model)
if connection.features.uses_case_insensitive_names:
converter = lambda x: x.upper()
else:
converter = lambda x: x
return set([m for m in all_models if converter(m._meta.db_table) in map(converter, table_list)])
def sequence_list():
"Returns a list of information about all DB sequences for all models in all apps."
from django.db import models
apps = models.get_apps()
sequence_list = []
for app in apps:
for model in models.get_models(app):
for f in model._meta.fields:
if isinstance(f, models.AutoField):
sequence_list.append({'table': model._meta.db_table, 'column': f.column})
break # Only one AutoField is allowed per model, so don't bother continuing.
for f in model._meta.many_to_many:
sequence_list.append({'table': f.m2m_db_table(), 'column': None})
return sequence_list
def sql_create(app, style):
"Returns a list of the CREATE TABLE SQL statements for the given app."
from django.db import models
from django.conf import settings
if settings.DATABASE_ENGINE == 'dummy':
# This must be the "dummy" database backend, which means the user
# hasn't set DATABASE_ENGINE.
raise CommandError("Django doesn't know which syntax to use for your SQL statements,\n" +
"because you haven't specified the DATABASE_ENGINE setting.\n" +
"Edit your settings file and change DATABASE_ENGINE to something like 'postgresql' or 'mysql'.")
# Get installed models, so we generate REFERENCES right.
# We trim models from the current app so that the sqlreset command does not
# generate invalid SQL (leaving models out of known_models is harmless, so
# we can be conservative).
app_models = models.get_models(app)
final_output = []
known_models = set([model for model in installed_models(table_list()) if model not in app_models])
pending_references = {}
for model in app_models:
output, references = sql_model_create(model, style, known_models)
final_output.extend(output)
for refto, refs in references.items():
pending_references.setdefault(refto, []).extend(refs)
if refto in known_models:
final_output.extend(sql_for_pending_references(refto, style, pending_references))
final_output.extend(sql_for_pending_references(model, style, pending_references))
# Keep track of the fact that we've created the table for this model.
known_models.add(model)
# Create the many-to-many join tables.
for model in app_models:
final_output.extend(many_to_many_sql_for_model(model, style))
# Handle references to tables that are from other apps
# but don't exist physically.
not_installed_models = set(pending_references.keys())
if not_installed_models:
alter_sql = []
for model in not_installed_models:
alter_sql.extend(['-- ' + sql for sql in
sql_for_pending_references(model, style, pending_references)])
if alter_sql:
final_output.append('-- The following references should be added but depend on non-existent tables:')
final_output.extend(alter_sql)
return final_output
def sql_delete(app, style):
"Returns a list of the DROP TABLE SQL statements for the given app."
from django.db import connection, models, get_introspection_module
from django.db.backends.util import truncate_name
from django.contrib.contenttypes import generic
introspection = get_introspection_module()
# This should work even if a connection isn't available
try:
cursor = connection.cursor()
except:
cursor = None
# Figure out which tables already exist
if cursor:
table_names = introspection.get_table_list(cursor)
else:
table_names = []
if connection.features.uses_case_insensitive_names:
table_name_converter = lambda x: x.upper()
else:
table_name_converter = lambda x: x
output = []
qn = connection.ops.quote_name
# Output DROP TABLE statements for standard application tables.
to_delete = set()
references_to_delete = {}
app_models = models.get_models(app)
for model in app_models:
if cursor and table_name_converter(model._meta.db_table) in table_names:
# The table exists, so it needs to be dropped
opts = model._meta
for f in opts.fields:
if f.rel and f.rel.to not in to_delete:
references_to_delete.setdefault(f.rel.to, []).append( (model, f) )
to_delete.add(model)
for model in app_models:
if cursor and table_name_converter(model._meta.db_table) in table_names:
# Drop the table now
output.append('%s %s;' % (style.SQL_KEYWORD('DROP TABLE'),
style.SQL_TABLE(qn(model._meta.db_table))))
if connection.features.supports_constraints and model in references_to_delete:
for rel_class, f in references_to_delete[model]:
table = rel_class._meta.db_table
col = f.column
r_table = model._meta.db_table
r_col = model._meta.get_field(f.rel.field_name).column
r_name = '%s_refs_%s_%x' % (col, r_col, abs(hash((table, r_table))))
output.append('%s %s %s %s;' % \
(style.SQL_KEYWORD('ALTER TABLE'),
style.SQL_TABLE(qn(table)),
style.SQL_KEYWORD(connection.ops.drop_foreignkey_sql()),
style.SQL_FIELD(truncate_name(r_name, connection.ops.max_name_length()))))
del references_to_delete[model]
if model._meta.has_auto_field:
ds = connection.ops.drop_sequence_sql(model._meta.db_table)
if ds:
output.append(ds)
# Output DROP TABLE statements for many-to-many tables.
for model in app_models:
opts = model._meta
for f in opts.many_to_many:
if isinstance(f.rel, generic.GenericRel):
continue
if cursor and table_name_converter(f.m2m_db_table()) in table_names:
output.append("%s %s;" % (style.SQL_KEYWORD('DROP TABLE'),
style.SQL_TABLE(qn(f.m2m_db_table()))))
ds = connection.ops.drop_sequence_sql("%s_%s" % (model._meta.db_table, f.column))
if ds:
output.append(ds)
app_label = app_models[0]._meta.app_label
# Close database connection explicitly, in case this output is being piped
# directly into a database client, to avoid locking issues.
if cursor:
cursor.close()
connection.close()
return output[::-1] # Reverse it, to deal with table dependencies.
def sql_reset(app, style):
"Returns a list of the DROP TABLE SQL, then the CREATE TABLE SQL, for the given module."
return sql_delete(app, style) + sql_all(app, style)
def sql_flush(style, only_django=False):
"""
Returns a list of the SQL statements used to flush the database.
If only_django is True, then only table names that have associated Django
models and are in INSTALLED_APPS will be included.
"""
from django.db import connection
if only_django:
tables = django_table_list()
else:
tables = table_list()
statements = connection.ops.sql_flush(style, tables, sequence_list())
return statements
def sql_custom(app):
"Returns a list of the custom table modifying SQL statements for the given app."
from django.db.models import get_models
output = []
app_models = get_models(app)
app_dir = os.path.normpath(os.path.join(os.path.dirname(app.__file__), 'sql'))
for model in app_models:
output.extend(custom_sql_for_model(model))
return output
def sql_indexes(app, style):
"Returns a list of the CREATE INDEX SQL statements for all models in the given app."
from django.db import models
output = []
for model in models.get_models(app):
output.extend(sql_indexes_for_model(model, style))
return output
def sql_all(app, style):
"Returns a list of CREATE TABLE SQL, initial-data inserts, and CREATE INDEX SQL for the given module."
return sql_create(app, style) + sql_custom(app) + sql_indexes(app, style)
def sql_model_create(model, style, known_models=set()):
"""
Returns the SQL required to create a single model, as a tuple of:
(list_of_sql, pending_references_dict)
"""
from django.db import connection, models
opts = model._meta
final_output = []
table_output = []
pending_references = {}
qn = connection.ops.quote_name
inline_references = connection.features.inline_fk_references
for f in opts.fields:
col_type = f.db_type()
tablespace = f.db_tablespace or opts.db_tablespace
if col_type is None:
# Skip ManyToManyFields, because they're not represented as
# database columns in this table.
continue
# Make the definition (e.g. 'foo VARCHAR(30)') for this field.
field_output = [style.SQL_FIELD(qn(f.column)),
style.SQL_COLTYPE(col_type)]
field_output.append(style.SQL_KEYWORD('%sNULL' % (not f.null and 'NOT ' or '')))
if f.unique and (not f.primary_key or connection.features.allows_unique_and_pk):
field_output.append(style.SQL_KEYWORD('UNIQUE'))
if f.primary_key:
field_output.append(style.SQL_KEYWORD('PRIMARY KEY'))
if tablespace and connection.features.supports_tablespaces and (f.unique or f.primary_key) and connection.features.autoindexes_primary_keys:
# We must specify the index tablespace inline, because we
# won't be generating a CREATE INDEX statement for this field.
field_output.append(connection.ops.tablespace_sql(tablespace, inline=True))
if f.rel:
if inline_references and f.rel.to in known_models:
field_output.append(style.SQL_KEYWORD('REFERENCES') + ' ' + \
style.SQL_TABLE(qn(f.rel.to._meta.db_table)) + ' (' + \
style.SQL_FIELD(qn(f.rel.to._meta.get_field(f.rel.field_name).column)) + ')' +
connection.ops.deferrable_sql()
)
else:
# We haven't yet created the table to which this field
# is related, so save it for later.
pr = pending_references.setdefault(f.rel.to, []).append((model, f))
table_output.append(' '.join(field_output))
if opts.order_with_respect_to:
table_output.append(style.SQL_FIELD(qn('_order')) + ' ' + \
style.SQL_COLTYPE(models.IntegerField().db_type()) + ' ' + \
style.SQL_KEYWORD('NULL'))
for field_constraints in opts.unique_together:
table_output.append(style.SQL_KEYWORD('UNIQUE') + ' (%s)' % \
", ".join([style.SQL_FIELD(qn(opts.get_field(f).column)) for f in field_constraints]))
full_statement = [style.SQL_KEYWORD('CREATE TABLE') + ' ' + style.SQL_TABLE(qn(opts.db_table)) + ' (']
for i, line in enumerate(table_output): # Combine and add commas.
full_statement.append(' %s%s' % (line, i < len(table_output)-1 and ',' or ''))
full_statement.append(')')
if opts.db_tablespace and connection.features.supports_tablespaces:
full_statement.append(connection.ops.tablespace_sql(opts.db_tablespace))
full_statement.append(';')
final_output.append('\n'.join(full_statement))
if opts.has_auto_field:
# Add any extra SQL needed to support auto-incrementing primary keys.
auto_column = opts.auto_field.db_column or opts.auto_field.name
autoinc_sql = connection.ops.autoinc_sql(opts.db_table, auto_column)
if autoinc_sql:
for stmt in autoinc_sql:
final_output.append(stmt)
return final_output, pending_references
def sql_for_pending_references(model, style, pending_references):
"""
Returns any ALTER TABLE statements to add constraints after the fact.
"""
from django.db import connection
from django.db.backends.util import truncate_name
qn = connection.ops.quote_name
final_output = []
if connection.features.supports_constraints:
opts = model._meta
if model in pending_references:
for rel_class, f in pending_references[model]:
rel_opts = rel_class._meta
r_table = rel_opts.db_table
r_col = f.column
table = opts.db_table
col = opts.get_field(f.rel.field_name).column
# For MySQL, r_name must be unique in the first 64 characters.
# So we are careful with character usage here.
r_name = '%s_refs_%s_%x' % (r_col, col, abs(hash((r_table, table))))
final_output.append(style.SQL_KEYWORD('ALTER TABLE') + ' %s ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s)%s;' % \
(qn(r_table), truncate_name(r_name, connection.ops.max_name_length()),
qn(r_col), qn(table), qn(col),
connection.ops.deferrable_sql()))
del pending_references[model]
return final_output
def many_to_many_sql_for_model(model, style):
from django.db import connection, models
from django.contrib.contenttypes import generic
from django.db.backends.util import truncate_name
opts = model._meta
final_output = []
qn = connection.ops.quote_name
inline_references = connection.features.inline_fk_references
for f in opts.many_to_many:
if not isinstance(f.rel, generic.GenericRel):
tablespace = f.db_tablespace or opts.db_tablespace
if tablespace and connection.features.supports_tablespaces and connection.features.autoindexes_primary_keys:
tablespace_sql = ' ' + connection.ops.tablespace_sql(tablespace, inline=True)
else:
tablespace_sql = ''
table_output = [style.SQL_KEYWORD('CREATE TABLE') + ' ' + \
style.SQL_TABLE(qn(f.m2m_db_table())) + ' (']
table_output.append(' %s %s %s%s,' %
(style.SQL_FIELD(qn('id')),
style.SQL_COLTYPE(models.AutoField(primary_key=True).db_type()),
style.SQL_KEYWORD('NOT NULL PRIMARY KEY'),
tablespace_sql))
if inline_references:
deferred = []
table_output.append(' %s %s %s %s (%s)%s,' %
(style.SQL_FIELD(qn(f.m2m_column_name())),
style.SQL_COLTYPE(models.ForeignKey(model).db_type()),
style.SQL_KEYWORD('NOT NULL REFERENCES'),
style.SQL_TABLE(qn(opts.db_table)),
style.SQL_FIELD(qn(opts.pk.column)),
connection.ops.deferrable_sql()))
table_output.append(' %s %s %s %s (%s)%s,' %
(style.SQL_FIELD(qn(f.m2m_reverse_name())),
style.SQL_COLTYPE(models.ForeignKey(f.rel.to).db_type()),
style.SQL_KEYWORD('NOT NULL REFERENCES'),
style.SQL_TABLE(qn(f.rel.to._meta.db_table)),
style.SQL_FIELD(qn(f.rel.to._meta.pk.column)),
connection.ops.deferrable_sql()))
else:
table_output.append(' %s %s %s,' %
(style.SQL_FIELD(qn(f.m2m_column_name())),
style.SQL_COLTYPE(models.ForeignKey(model).db_type()),
style.SQL_KEYWORD('NOT NULL')))
table_output.append(' %s %s %s,' %
(style.SQL_FIELD(qn(f.m2m_reverse_name())),
style.SQL_COLTYPE(models.ForeignKey(f.rel.to).db_type()),
style.SQL_KEYWORD('NOT NULL')))
deferred = [
(f.m2m_db_table(), f.m2m_column_name(), opts.db_table,
opts.pk.column),
( f.m2m_db_table(), f.m2m_reverse_name(),
f.rel.to._meta.db_table, f.rel.to._meta.pk.column)
]
table_output.append(' %s (%s, %s)%s' %
(style.SQL_KEYWORD('UNIQUE'),
style.SQL_FIELD(qn(f.m2m_column_name())),
style.SQL_FIELD(qn(f.m2m_reverse_name())),
tablespace_sql))
table_output.append(')')
if opts.db_tablespace and connection.features.supports_tablespaces:
# f.db_tablespace is only for indices, so ignore its value here.
table_output.append(connection.ops.tablespace_sql(opts.db_tablespace))
table_output.append(';')
final_output.append('\n'.join(table_output))
for r_table, r_col, table, col in deferred:
r_name = '%s_refs_%s_%x' % (r_col, col,
abs(hash((r_table, table))))
final_output.append(style.SQL_KEYWORD('ALTER TABLE') + ' %s ADD CONSTRAINT %s FOREIGN KEY (%s) REFERENCES %s (%s)%s;' %
(qn(r_table),
truncate_name(r_name, connection.ops.max_name_length()),
qn(r_col), qn(table), qn(col),
connection.ops.deferrable_sql()))
# Add any extra SQL needed to support auto-incrementing PKs
autoinc_sql = connection.ops.autoinc_sql(f.m2m_db_table(), 'id')
if autoinc_sql:
for stmt in autoinc_sql:
final_output.append(stmt)
return final_output
def custom_sql_for_model(model):
from django.db import models
from django.conf import settings
opts = model._meta
app_dir = os.path.normpath(os.path.join(os.path.dirname(models.get_app(model._meta.app_label).__file__), 'sql'))
output = []
# Some backends can't execute more than one SQL statement at a time,
# so split into separate statements.
statements = re.compile(r";[ \t]*$", re.M)
# Find custom SQL, if it's available.
sql_files = [os.path.join(app_dir, "%s.%s.sql" % (opts.object_name.lower(), settings.DATABASE_ENGINE)),
os.path.join(app_dir, "%s.sql" % opts.object_name.lower())]
for sql_file in sql_files:
if os.path.exists(sql_file):
fp = open(sql_file, 'U')
for statement in statements.split(fp.read().decode(settings.FILE_CHARSET)):
# Remove any comments from the file
statement = re.sub(ur"--.*[\n\Z]", "", statement)
if statement.strip():
output.append(statement + u";")
fp.close()
return output
def sql_indexes_for_model(model, style):
"Returns the CREATE INDEX SQL statements for a single model"
from django.db import connection
output = []
qn = connection.ops.quote_name
for f in model._meta.fields:
if f.db_index and not ((f.primary_key or f.unique) and connection.features.autoindexes_primary_keys):
unique = f.unique and 'UNIQUE ' or ''
tablespace = f.db_tablespace or model._meta.db_tablespace
if tablespace and connection.features.supports_tablespaces:
tablespace_sql = ' ' + connection.ops.tablespace_sql(tablespace)
else:
tablespace_sql = ''
output.append(
style.SQL_KEYWORD('CREATE %sINDEX' % unique) + ' ' + \
style.SQL_TABLE(qn('%s_%s' % (model._meta.db_table, f.column))) + ' ' + \
style.SQL_KEYWORD('ON') + ' ' + \
style.SQL_TABLE(qn(model._meta.db_table)) + ' ' + \
"(%s)" % style.SQL_FIELD(qn(f.column)) + \
"%s;" % tablespace_sql
)
return output
def emit_post_sync_signal(created_models, verbosity, interactive):
from django.db import models
from django.dispatch import dispatcher
# Emit the post_sync signal for every application.
for app in models.get_apps():
app_name = app.__name__.split('.')[-2]
if verbosity >= 2:
print "Running post-sync handlers for application", app_name
dispatcher.send(signal=models.signals.post_syncdb, sender=app,
app=app, created_models=created_models,
verbosity=verbosity, interactive=interactive)