FlaskSQLAlchemy query very slow
0
I'm facing a problem concerning performance when using the FlaskSQLAlchemy query function. With a database size of ca. 400 MB, a query containing all elements takes nearly 100 seconds.
Here is the query:
start_time = time.time()
results = DataPoint.query.all()
end_time = time.time()
print("All Datapoints: ", results)
print("Number of elements:", len(results))
print("Time elapsed: ", end_time-start_time)
Output: Number of elements: 5871988
Time elapsed: 96.98983788490295
with DataPoint being:
class DataPoint(db.Model):
id = db.Column(db.Integer, primary_key=True)
sensor_type = db.Column(db.String(75), nullable=False)
sensor_number = db.Column(db.Integer)
serial_number = db.Column(db.Float, db.ForeignKey('sensor_box.serial_number'), nullable=False)
sensor_value = db.Column(db.Float, nullable=False)
date_time = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
is this long duration normal, or am I doing something wrong?
Thanks in advance
python sqlalchemy flask-sqlalchemy
edited Nov 25 '18 at 13:04
davidism
65.1k12172188
asked Nov 25 '18 at 12:32
zerocoolzerocool
204
add a comment |
0
I'm facing a problem concerning performance when using the FlaskSQLAlchemy query function. With a database size of ca. 400 MB, a query containing all elements takes nearly 100 seconds.
Here is the query:
start_time = time.time()
results = DataPoint.query.all()
end_time = time.time()
print("All Datapoints: ", results)
print("Number of elements:", len(results))
print("Time elapsed: ", end_time-start_time)
Output: Number of elements: 5871988
Time elapsed: 96.98983788490295
with DataPoint being:
class DataPoint(db.Model):
id = db.Column(db.Integer, primary_key=True)
sensor_type = db.Column(db.String(75), nullable=False)
sensor_number = db.Column(db.Integer)
serial_number = db.Column(db.Float, db.ForeignKey('sensor_box.serial_number'), nullable=False)
sensor_value = db.Column(db.Float, nullable=False)
date_time = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
is this long duration normal, or am I doing something wrong?
Thanks in advance
python sqlalchemy flask-sqlalchemy
edited Nov 25 '18 at 13:04
davidism
65.1k12172188
asked Nov 25 '18 at 12:32
zerocoolzerocool
204
2
ORMs do sacrifice performance for convenience. There are a lot of variables that can play into this, size of the result set, available memory, is the database remote or local etc.. There is a whole page in the docs about ORM query performance, with a particular section about ORM Selects.
– SuperShoot
Nov 25 '18 at 12:38
1
Did you try this: stackoverflow.com/questions/33738467/…
– Ganesh K
Nov 25 '18 at 12:45
yes I set it to False, thx
– zerocool
Nov 25 '18 at 12:45
add a comment |
0
0
0
I'm facing a problem concerning performance when using the FlaskSQLAlchemy query function. With a database size of ca. 400 MB, a query containing all elements takes nearly 100 seconds.
Here is the query:
start_time = time.time()
results = DataPoint.query.all()
end_time = time.time()
print("All Datapoints: ", results)
print("Number of elements:", len(results))
print("Time elapsed: ", end_time-start_time)
Output: Number of elements: 5871988
Time elapsed: 96.98983788490295
with DataPoint being:
class DataPoint(db.Model):
id = db.Column(db.Integer, primary_key=True)
sensor_type = db.Column(db.String(75), nullable=False)
sensor_number = db.Column(db.Integer)
serial_number = db.Column(db.Float, db.ForeignKey('sensor_box.serial_number'), nullable=False)
sensor_value = db.Column(db.Float, nullable=False)
date_time = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
is this long duration normal, or am I doing something wrong?
Thanks in advance
python sqlalchemy flask-sqlalchemy
edited Nov 25 '18 at 13:04
davidism
65.1k12172188
asked Nov 25 '18 at 12:32
zerocoolzerocool
204
I'm facing a problem concerning performance when using the FlaskSQLAlchemy query function. With a database size of ca. 400 MB, a query containing all elements takes nearly 100 seconds.
Here is the query:
start_time = time.time()
results = DataPoint.query.all()
end_time = time.time()
print("All Datapoints: ", results)
print("Number of elements:", len(results))
print("Time elapsed: ", end_time-start_time)
Output: Number of elements: 5871988
Time elapsed: 96.98983788490295
with DataPoint being:
class DataPoint(db.Model):
id = db.Column(db.Integer, primary_key=True)
sensor_type = db.Column(db.String(75), nullable=False)
sensor_number = db.Column(db.Integer)
serial_number = db.Column(db.Float, db.ForeignKey('sensor_box.serial_number'), nullable=False)
sensor_value = db.Column(db.Float, nullable=False)
date_time = db.Column(db.DateTime, nullable=False, default=datetime.utcnow)
is this long duration normal, or am I doing something wrong?
Thanks in advance
python sqlalchemy flask-sqlalchemy
python sqlalchemy flask-sqlalchemy
edited Nov 25 '18 at 13:04
davidism
65.1k12172188
asked Nov 25 '18 at 12:32
zerocoolzerocool
204
edited Nov 25 '18 at 13:04
davidism
65.1k12172188
asked Nov 25 '18 at 12:32
zerocoolzerocool
204
edited Nov 25 '18 at 13:04
davidism
65.1k12172188
edited Nov 25 '18 at 13:04
davidism
65.1k12172188
edited Nov 25 '18 at 13:04
davidism
65.1k12172188
65.1k12172188
asked Nov 25 '18 at 12:32
zerocoolzerocool
204
asked Nov 25 '18 at 12:32
zerocoolzerocool
204
asked Nov 25 '18 at 12:32
zerocoolzerocool
204
204
2
ORMs do sacrifice performance for convenience. There are a lot of variables that can play into this, size of the result set, available memory, is the database remote or local etc.. There is a whole page in the docs about ORM query performance, with a particular section about ORM Selects.
– SuperShoot
Nov 25 '18 at 12:38
1
Did you try this: stackoverflow.com/questions/33738467/…
– Ganesh K
Nov 25 '18 at 12:45
yes I set it to False, thx
– zerocool
Nov 25 '18 at 12:45
add a comment |
2
ORMs do sacrifice performance for convenience. There are a lot of variables that can play into this, size of the result set, available memory, is the database remote or local etc.. There is a whole page in the docs about ORM query performance, with a particular section about ORM Selects.
– SuperShoot
Nov 25 '18 at 12:38
1
Did you try this: stackoverflow.com/questions/33738467/…
– Ganesh K
Nov 25 '18 at 12:45
yes I set it to False, thx
– zerocool
Nov 25 '18 at 12:45
2
2
ORMs do sacrifice performance for convenience. There are a lot of variables that can play into this, size of the result set, available memory, is the database remote or local etc.. There is a whole page in the docs about ORM query performance, with a particular section about ORM Selects.
– SuperShoot
Nov 25 '18 at 12:38
ORMs do sacrifice performance for convenience. There are a lot of variables that can play into this, size of the result set, available memory, is the database remote or local etc.. There is a whole page in the docs about ORM query performance, with a particular section about ORM Selects.
– SuperShoot
Nov 25 '18 at 12:38
1
1
Did you try this: stackoverflow.com/questions/33738467/…
– Ganesh K
Nov 25 '18 at 12:45
Did you try this: stackoverflow.com/questions/33738467/…
– Ganesh K
Nov 25 '18 at 12:45
yes I set it to False, thx
– zerocool
Nov 25 '18 at 12:45
yes I set it to False, thx
– zerocool
Nov 25 '18 at 12:45
add a comment |
0
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2
ORMs do sacrifice performance for convenience. There are a lot of variables that can play into this, size of the result set, available memory, is the database remote or local etc.. There is a whole page in the docs about ORM query performance, with a particular section about ORM Selects.
– SuperShoot
Nov 25 '18 at 12:38
1
Did you try this: stackoverflow.com/questions/33738467/…
– Ganesh K
Nov 25 '18 at 12:45
yes I set it to False, thx
– zerocool
Nov 25 '18 at 12:45