sqlalchemy_singlestoredb.ColumnGroup¶

class sqlalchemy_singlestoredb.ColumnGroup(*, name: str | None = None)¶

SingleStore COLUMN GROUP DDL element.

Represents a COLUMN GROUP constraint that creates a materialized copy of each row as a separate index for columnstore tables, improving full-row retrieval/update on wide tables.

Parameters:: name (str, optional, keyword-only) – Optional name for the column group. If not provided, SingleStore will auto-generate a name. Must be passed as a keyword argument if specified.

Examples

Column group with name:

>>> ColumnGroup(name='cg_all_columns')

Column group without explicit name (auto-generated):

>>> ColumnGroup()

Table Usage:

from sqlalchemy import Column, Integer, MetaData, String, Table
from sqlalchemy_singlestoredb import ColumnGroup, ColumnStore
metadata = MetaData()
wide_table = Table(
    'wide_table', metadata,
    Column('id', Integer, primary_key=True),
    Column('col1', String(100)),
    Column('col2', String(100)),
    singlestoredb_table_type=ColumnStore(),
    singlestoredb_column_group=ColumnGroup(name='cg_all'),
)
# Column group with auto-generated name
analytics = Table(
    'analytics', metadata,
    Column('id', Integer, primary_key=True),
    Column('data', String(255)),
    singlestoredb_table_type=ColumnStore(),
    singlestoredb_column_group=ColumnGroup(),
)

ORM Usage:

from sqlalchemy import Column, Integer, String
from sqlalchemy.orm import declarative_base
from sqlalchemy_singlestoredb import ColumnGroup, ColumnStore
Base = declarative_base()
class WideTable(Base):
    __tablename__ = 'wide_table'
    id = Column(Integer, primary_key=True)
    col1 = Column(String(100))
    col2 = Column(String(100))
    __table_args__ = {
        'singlestoredb_table_type': ColumnStore(),
        'singlestoredb_column_group': ColumnGroup(name='cg_all'),
    }
class Analytics(Base):
    __tablename__ = 'analytics'
    id = Column(Integer, primary_key=True)
    data = Column(String(255))
    __table_args__ = {
        'singlestoredb_table_type': ColumnStore(),
        'singlestoredb_column_group': ColumnGroup(),
    }

Notes

Only supported on columnstore tables
Automatically applies to all columns (uses * syntax)
Subset column groups are not supported by SingleStore
Improves full-row retrieval/update performance on wide tables
Uses less RAM than rowstore for similar use cases
If name is not provided, SingleStore will auto-generate one

__init__(*, name: str | None = None) → None¶

Methods

`__init__`(*[, name])
`against`(target)	Return a copy of this `_schema.ExecutableDDLElement` which will include the given target.
`compare`(other, **kw)	Compare this `_expression.ClauseElement` to the given `_expression.ClauseElement`.
`compile`([bind, dialect])	Compile this SQL expression.
`execute_if`([dialect, callable_, state])	Return a callable that will execute this `_ddl.ExecutableDDLElement` conditionally within an event handler.
`execution_options`(**kw)	Set non-SQL options for the statement which take effect during execution.
`get_children`(*[, omit_attrs])	Return immediate child `visitors.HasTraverseInternals` elements of this `visitors.HasTraverseInternals`.
`get_execution_options`()	Get the non-SQL options which will take effect during execution.
`memoized_instancemethod`(fn)	Decorate a method memoize its return value.
`options`(*options)	Apply options to this statement.
`params`([_ClauseElement__optionaldict])	Return a copy with `_expression.bindparam()` elements replaced.
`self_group`([against])	Apply a 'grouping' to this `_expression.ClauseElement`.
`unique_params`([_ClauseElement__optionaldict])	Return a copy with `_expression.bindparam()` elements replaced.

Attributes

`allows_lambda`
`description`
`entity_namespace`
`inherit_cache`	Indicate if this `HasCacheKey` instance should make use of the cache key generation scheme used by its immediate superclass.
`is_clause_element`
`is_delete`
`is_dml`
`is_from_statement`
`is_insert`
`is_select`
`is_selectable`
`is_text`
`is_update`
`stringify_dialect`
`supports_execution`
`target`
`uses_inspection`
`name`
`negation_clause`
`proxy_set`