Source code for server.contrib.postgres.indexes

from server.db.models import Index
from server.db.utils import NotSupportedError
from server.utils.functional import cached_property

__all__ = [
    'BrinIndex', 'BTreeIndex', 'GinIndex', 'GistIndex', 'HashIndex',
    'SpGistIndex',
]


class PostgresIndex(Index):

    @cached_property
    def max_name_length(self):
        # Allow an index name longer than 30 characters when the suffix is
        # longer than the usual 3 character limit. The 30 character limit for
        # cross-database compatibility isn't applicable to PostgreSQL-specific
        # indexes.
        return Index.max_name_length - len(Index.suffix) + len(self.suffix)

    def create_sql(self, model, schema_editor, using=''):
        self.check_supported(schema_editor)
        statement = super().create_sql(model, schema_editor, using=' USING %s' % self.suffix)
        with_params = self.get_with_params()
        if with_params:
            statement.parts['extra'] = 'WITH (%s) %s' % (
                ', '.join(with_params),
                statement.parts['extra'],
            )
        return statement

    def check_supported(self, schema_editor):
        pass

    def get_with_params(self):
        return []


[docs]class BrinIndex(PostgresIndex): suffix = 'brin' def __init__(self, *, autosummarize=None, pages_per_range=None, **kwargs): if pages_per_range is not None and pages_per_range <= 0: raise ValueError('pages_per_range must be None or a positive integer') self.autosummarize = autosummarize self.pages_per_range = pages_per_range super().__init__(**kwargs) def deconstruct(self): path, args, kwargs = super().deconstruct() if self.autosummarize is not None: kwargs['autosummarize'] = self.autosummarize if self.pages_per_range is not None: kwargs['pages_per_range'] = self.pages_per_range return path, args, kwargs def check_supported(self, schema_editor): if self.autosummarize and not schema_editor.connection.features.has_brin_autosummarize: raise NotSupportedError('BRIN option autosummarize requires PostgreSQL 10+.') def get_with_params(self): with_params = [] if self.autosummarize is not None: with_params.append('autosummarize = %s' % ('on' if self.autosummarize else 'off')) if self.pages_per_range is not None: with_params.append('pages_per_range = %d' % self.pages_per_range) return with_params
[docs]class BTreeIndex(PostgresIndex): suffix = 'btree' def __init__(self, *, fillfactor=None, **kwargs): self.fillfactor = fillfactor super().__init__(**kwargs) def deconstruct(self): path, args, kwargs = super().deconstruct() if self.fillfactor is not None: kwargs['fillfactor'] = self.fillfactor return path, args, kwargs def get_with_params(self): with_params = [] if self.fillfactor is not None: with_params.append('fillfactor = %d' % self.fillfactor) return with_params
[docs]class GinIndex(PostgresIndex): suffix = 'gin' def __init__(self, *, fastupdate=None, gin_pending_list_limit=None, **kwargs): self.fastupdate = fastupdate self.gin_pending_list_limit = gin_pending_list_limit super().__init__(**kwargs) def deconstruct(self): path, args, kwargs = super().deconstruct() if self.fastupdate is not None: kwargs['fastupdate'] = self.fastupdate if self.gin_pending_list_limit is not None: kwargs['gin_pending_list_limit'] = self.gin_pending_list_limit return path, args, kwargs def get_with_params(self): with_params = [] if self.gin_pending_list_limit is not None: with_params.append('gin_pending_list_limit = %d' % self.gin_pending_list_limit) if self.fastupdate is not None: with_params.append('fastupdate = %s' % ('on' if self.fastupdate else 'off')) return with_params
[docs]class GistIndex(PostgresIndex): suffix = 'gist' def __init__(self, *, buffering=None, fillfactor=None, **kwargs): self.buffering = buffering self.fillfactor = fillfactor super().__init__(**kwargs) def deconstruct(self): path, args, kwargs = super().deconstruct() if self.buffering is not None: kwargs['buffering'] = self.buffering if self.fillfactor is not None: kwargs['fillfactor'] = self.fillfactor return path, args, kwargs def get_with_params(self): with_params = [] if self.buffering is not None: with_params.append('buffering = %s' % ('on' if self.buffering else 'off')) if self.fillfactor is not None: with_params.append('fillfactor = %d' % self.fillfactor) return with_params
[docs]class HashIndex(PostgresIndex): suffix = 'hash' def __init__(self, *, fillfactor=None, **kwargs): self.fillfactor = fillfactor super().__init__(**kwargs) def deconstruct(self): path, args, kwargs = super().deconstruct() if self.fillfactor is not None: kwargs['fillfactor'] = self.fillfactor return path, args, kwargs def get_with_params(self): with_params = [] if self.fillfactor is not None: with_params.append('fillfactor = %d' % self.fillfactor) return with_params
[docs]class SpGistIndex(PostgresIndex): suffix = 'spgist' def __init__(self, *, fillfactor=None, **kwargs): self.fillfactor = fillfactor super().__init__(**kwargs) def deconstruct(self): path, args, kwargs = super().deconstruct() if self.fillfactor is not None: kwargs['fillfactor'] = self.fillfactor return path, args, kwargs def get_with_params(self): with_params = [] if self.fillfactor is not None: with_params.append('fillfactor = %d' % self.fillfactor) return with_params