def load_experiment_by_name(
name: str,
sample: Optional[str] = None,
conn: Optional[ConnectionPlus] = None) -> Experiment:
"""
Try to load experiment with the specified name.
Nothing stops you from having many experiments with the same name and
sample_name. In that case this won't work. And warn you.
Args:
name: the name of the experiment
sample: the name of the sample
conn: connection to the database. If not supplied, a new connection
to the DB file specified in the config is made
Returns:
the requested experiment
Raises:
ValueError if the name is not unique and sample name is None.
"""
conn = conn or connect(get_DB_location())
if sample:
sql = """
SELECT
*
FROM
experiments
WHERE
sample_name = ? AND
name = ?
"""
c = transaction(conn, sql, sample, name)
else:
sql = """
SELECT
*
FROM
experiments
WHERE
name = ?
"""
c = transaction(conn, sql, name)
rows = c.fetchall()
if len(rows) == 0:
raise ValueError("Experiment not found")
elif len(rows) > 1:
_repr = []
for row in rows:
s = (f"exp_id:{row['exp_id']} ({row['name']}-{row['sample_name']})"
f" started at ({row['start_time']})")
_repr.append(s)
_repr_str = "\n".join(_repr)
raise ValueError(f"Many experiments matching your request"
f" found:\n{_repr_str}")
else:
e = Experiment(exp_id=rows[0]['exp_id'], conn=conn)
return e
def test_atomic_raises(experiment):
conn = experiment.conn
bad_sql = '""'
# it seems that the type of error raised differs between python versions
# 3.6.0 (OperationalError) and 3.6.3 (RuntimeError)
# -strange, huh?
with pytest.raises((OperationalError, RuntimeError)):
with mut.atomic(conn):
mut.transaction(conn, bad_sql)
def load_experiment_by_name(name: str,
sample: Optional[str] = None) -> Experiment:
"""
Try to load experiment with the specified name.
Nothing stops you from having many experiments with
the same name and sample_name.
In that case this won't work. And warn you.
Args:
name: the name of the experiment
sample: the name of the sample
Returns:
the requested experiment
Raises:
ValueError if the name is not unique and sample name is None.
"""
e = Experiment(get_DB_location())
if sample:
sql = """
SELECT
*
FROM
experiments
WHERE
sample_name = ? AND
name = ?
"""
c = transaction(e.conn, sql, sample, name)
else:
sql = """
SELECT
*
FROM
experiments
WHERE
name = ?
"""
c = transaction(e.conn, sql, name)
rows = c.fetchall()
if len(rows) == 0:
raise ValueError("Experiment not found \n")
elif len(rows) > 1:
_repr = []
for row in rows:
s = f"exp_id:{row['exp_id']} ({row['name']}-{row['sample_name']}) started at({row['start_time']})"
_repr.append(s)
_repr_str = "\n".join(_repr)
raise ValueError(
f"Many experiments matching your request found {_repr_str}")
else:
e.exp_id = rows[0]['exp_id']
return e
def test_atomic_creation(experiment):
""""
Test that dataset creation is atomic. Test for
https://github.com/QCoDeS/Qcodes/issues/1444
"""
def just_throw(*args):
raise RuntimeError("This breaks adding metadata")
# first we patch add_meta_data to throw an exception
# if create_data is not atomic this would create a partial
# run in the db. Causing the next create_run to fail
with patch('qcodes.dataset.sqlite_base.add_meta_data', new=just_throw):
x = ParamSpec('x', 'numeric')
t = ParamSpec('t', 'numeric')
y = ParamSpec('y', 'numeric', depends_on=['x', 't'])
with pytest.raises(
RuntimeError,
match="Rolling back due to unhandled exception") as e:
mut.create_run(experiment.conn,
experiment.exp_id,
name='testrun',
guid=generate_guid(),
parameters=[x, t, y],
metadata={'a': 1})
assert error_caused_by(e, "This breaks adding metadata")
# since we are starting from an empty database and the above transaction
# should be rolled back there should be no runs in the run table
runs = mut.transaction(experiment.conn,
'SELECT run_id FROM runs').fetchall()
assert len(runs) == 0
with shadow_conn(experiment.path_to_db) as new_conn:
runs = mut.transaction(new_conn, 'SELECT run_id FROM runs').fetchall()
assert len(runs) == 0
# if the above was not correctly rolled back we
# expect the next creation of a run to fail
mut.create_run(experiment.conn,
experiment.exp_id,
name='testrun',
guid=generate_guid(),
parameters=[x, t, y],
metadata={'a': 1})
runs = mut.transaction(experiment.conn,
'SELECT run_id FROM runs').fetchall()
assert len(runs) == 1
with shadow_conn(experiment.path_to_db) as new_conn:
runs = mut.transaction(new_conn, 'SELECT run_id FROM runs').fetchall()
assert len(runs) == 1
def load_by_counter(counter, exp_id):
"""
Load a dataset given its counter in one experiment
Args:
counter: Counter of the dataset
exp_id: Experiment the dataset belongs to
Returns:
the dataset
"""
conn = connect(get_DB_location())
sql = """
SELECT run_id
FROM
runs
WHERE
result_counter= ? AND
exp_id = ?
"""
c = transaction(conn, sql, counter, exp_id)
run_id = one(c, 'run_id')
conn.close()
d = DataSet(get_DB_location(), run_id=run_id)
return d
def load_by_counter(counter: int,
exp_id: int,
conn: Optional[ConnectionPlus] = None) -> DataSet:
"""
Load a dataset given its counter in a given experiment
Lookup is performed in the database file that is specified in the config.
Args:
counter: counter of the dataset within the given experiment
exp_id: id of the experiment where to look for the dataset
conn: connection to the database to load from. If not provided, a
connection to the DB file specified in the config is made
Returns:
dataset of the given counter in the given experiment
"""
conn = conn or connect(get_DB_location())
sql = """
SELECT run_id
FROM
runs
WHERE
result_counter= ? AND
exp_id = ?
"""
c = transaction(conn, sql, counter, exp_id)
run_id = one(c, 'run_id')
d = DataSet(conn=conn, run_id=run_id)
return d
def get_run_timestamp(run_id):
DB = qc.config["core"]["db_location"]
d = DataSet(DB)
sql = """
SELECT run_timestamp
FROM
runs
WHERE
run_id= ?
"""
c = transaction(d.conn, sql, run_id)
run_timestamp = one(c, 'run_timestamp')
return run_timestamp
def load_by_counter(counter, exp_id):
"""
Load a dataset given its counter in one experiment
Args:
counter: Counter of the dataset
exp_id: Experiment the dataset belongs to
Returns:
the dataset
"""
d = DataSet(DB)
sql = """
SELECT run_id
FROM
runs
WHERE
result_counter= ? AND
exp_id = ?
"""
c = transaction(d.conn, sql, counter, exp_id)
d.run_id = one(c, 'run_id')
return d
def _remove_trigger(self, name):
transaction(self.conn, f"DROP TRIGGER IF EXISTS {name};")
