diff options
Diffstat (limited to 'lib/sqlalchemy/sql/expression.py')
| -rw-r--r-- | lib/sqlalchemy/sql/expression.py | 36 |
1 files changed, 25 insertions, 11 deletions
diff --git a/lib/sqlalchemy/sql/expression.py b/lib/sqlalchemy/sql/expression.py index 6a368b8c0..8a9d33d55 100644 --- a/lib/sqlalchemy/sql/expression.py +++ b/lib/sqlalchemy/sql/expression.py @@ -2563,9 +2563,7 @@ class Executable(_Generative): """ Set non-SQL options for the statement which take effect during execution. - Current options include: - - * autocommit - when True, a COMMIT will be invoked after execution + :param autocommit: when True, a COMMIT will be invoked after execution when executed in 'autocommit' mode, i.e. when an explicit transaction is not begun on the connection. Note that DBAPI connections by default are always in a transaction - SQLAlchemy uses @@ -2577,15 +2575,15 @@ class Executable(_Generative): specific SQL construct where COMMIT is desired (typically when calling stored procedures and such). - * stream_results - indicate to the dialect that results should be + :param stream_results: indicate to the dialect that results should be "streamed" and not pre-buffered, if possible. This is a limitation of many DBAPIs. The flag is currently understood only by the psycopg2 dialect. - * compiled_cache - a dictionary where :class:`Compiled` objects - will be cached when the :class:`Connection` compiles a clause + :param compiled_cache: a dictionary where :class:`.Compiled` objects + will be cached when the :class:`.Connection` compiles a clause expression into a dialect- and parameter-specific - :class:`Compiled` object. It is the user's responsibility to + :class:`.Compiled` object. It is the user's responsibility to manage the size of this dictionary, which will have keys corresponding to the dialect, clause element, the column names within the VALUES or SET clause of an INSERT or UPDATE, @@ -2595,17 +2593,33 @@ class Executable(_Generative): This option is usually more appropriate to use via the - :meth:`sqlalchemy.engine.base.Connection.execution_options()` - method of :class:`Connection`, rather than upon individual + :meth:`.Connection.execution_options()` + method of :class:`.Connection`, rather than upon individual statement objects, though the effect is the same. + + Note that the ORM makes use of its own "compiled" caches for + some operations, including flush operations. The caching + used by the ORM internally supercedes a cache dictionary + specified here. See also: - :meth:`sqlalchemy.engine.base.Connection.execution_options()` + :meth:`.Connection.execution_options()` - + includes a connection-only option to specify transaction isolation + level. - :meth:`sqlalchemy.orm.query.Query.execution_options()` + :meth:`.Query.execution_options()` - applies options to the statement + generated by a :class:`.orm.Query` object. """ + if 'isolation_level' in kw: + raise exc.ArgumentError( + "'isolation_level' execution option may only be specified " + "on Connection.execution_options(), or " + "per-engine using the isolation_level " + "argument to create_engine()." + ) + self._execution_options = self._execution_options.union(kw) def execute(self, *multiparams, **params): |