SQL Alchemy timing out when executing large query
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I have a large query to execute through SQL Alchemy which has approximately 2.5 million rows. It's connecting to a MySQL database. When I do:
transactions = Transaction.query.all()
It eventually times out around ten minutes. And gets this error: sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2013, 'Lost connection to MySQL server during query')
I've tried setting different parameters when doing create_engine like:
create_engine(connect_args={'connect_timeout': 30})
What do I need to change so the query will not timeout?
I would also be fine if there is a way to paginate the results and go through them that way.
mysql sqlalchemy
asked Nov 23 '18 at 14:24
William RossWilliam Ross
86321141
add a comment |
I have a large query to execute through SQL Alchemy which has approximately 2.5 million rows. It's connecting to a MySQL database. When I do:
transactions = Transaction.query.all()
It eventually times out around ten minutes. And gets this error: sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2013, 'Lost connection to MySQL server during query')
I've tried setting different parameters when doing create_engine like:
create_engine(connect_args={'connect_timeout': 30})
What do I need to change so the query will not timeout?
I would also be fine if there is a way to paginate the results and go through them that way.
mysql sqlalchemy
asked Nov 23 '18 at 14:24
William RossWilliam Ross
86321141
1
There is a page in the MySQL docs that might help you with debugging.
– SuperShoot
Nov 23 '18 at 21:21
1
Also this answer covers pagination.
– SuperShoot
Nov 23 '18 at 21:23
add a comment |
I have a large query to execute through SQL Alchemy which has approximately 2.5 million rows. It's connecting to a MySQL database. When I do:
transactions = Transaction.query.all()
It eventually times out around ten minutes. And gets this error: sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2013, 'Lost connection to MySQL server during query')
I've tried setting different parameters when doing create_engine like:
create_engine(connect_args={'connect_timeout': 30})
What do I need to change so the query will not timeout?
I would also be fine if there is a way to paginate the results and go through them that way.
mysql sqlalchemy
asked Nov 23 '18 at 14:24
William RossWilliam Ross
86321141
I have a large query to execute through SQL Alchemy which has approximately 2.5 million rows. It's connecting to a MySQL database. When I do:
transactions = Transaction.query.all()
It eventually times out around ten minutes. And gets this error: sqlalchemy.exc.OperationalError: (pymysql.err.OperationalError) (2013, 'Lost connection to MySQL server during query')
I've tried setting different parameters when doing create_engine like:
create_engine(connect_args={'connect_timeout': 30})
What do I need to change so the query will not timeout?
I would also be fine if there is a way to paginate the results and go through them that way.
mysql sqlalchemy
mysql sqlalchemy
asked Nov 23 '18 at 14:24
William RossWilliam Ross
86321141
asked Nov 23 '18 at 14:24
William RossWilliam Ross
86321141
edited Nov 23 '18 at 14:34
William Ross
asked Nov 23 '18 at 14:24
William RossWilliam Ross
86321141
asked Nov 23 '18 at 14:24
William RossWilliam Ross
86321141
asked Nov 23 '18 at 14:24
William RossWilliam Ross
86321141
86321141
1
There is a page in the MySQL docs that might help you with debugging.
– SuperShoot
Nov 23 '18 at 21:21
1
Also this answer covers pagination.
– SuperShoot
Nov 23 '18 at 21:23
add a comment |
1
There is a page in the MySQL docs that might help you with debugging.
– SuperShoot
Nov 23 '18 at 21:21
1
Also this answer covers pagination.
– SuperShoot
Nov 23 '18 at 21:23
1
1
There is a page in the MySQL docs that might help you with debugging.
– SuperShoot
Nov 23 '18 at 21:21
There is a page in the MySQL docs that might help you with debugging.
– SuperShoot
Nov 23 '18 at 21:21
1
1
Also this answer covers pagination.
– SuperShoot
Nov 23 '18 at 21:23
Also this answer covers pagination.
– SuperShoot
Nov 23 '18 at 21:23
add a comment |
1 Answer
1
active
oldest
votes
Solved by pagination:
page_size = 10000 # get x number of items at a time
step = 0
while True:
start, stop = page_size * step, page_size * (step+1)
transactions = sql_session.query(Transaction).slice(start, stop).all()
if transactions is None:
break
for t in transactions:
f.write(str(t))
f.write('n')
if len(transactions) < page_size:
break
step += 1
f.close()
answered Nov 29 '18 at 15:02
William RossWilliam Ross
86321141
add a comment |
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1 Answer
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oldest
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1 Answer
1
active
oldest
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active
oldest
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oldest
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Solved by pagination:
page_size = 10000 # get x number of items at a time
step = 0
while True:
start, stop = page_size * step, page_size * (step+1)
transactions = sql_session.query(Transaction).slice(start, stop).all()
if transactions is None:
break
for t in transactions:
f.write(str(t))
f.write('n')
if len(transactions) < page_size:
break
step += 1
f.close()
answered Nov 29 '18 at 15:02
William RossWilliam Ross
86321141
add a comment |
Solved by pagination:
page_size = 10000 # get x number of items at a time
step = 0
while True:
start, stop = page_size * step, page_size * (step+1)
transactions = sql_session.query(Transaction).slice(start, stop).all()
if transactions is None:
break
for t in transactions:
f.write(str(t))
f.write('n')
if len(transactions) < page_size:
break
step += 1
f.close()
answered Nov 29 '18 at 15:02
William RossWilliam Ross
86321141
add a comment |
Solved by pagination:
page_size = 10000 # get x number of items at a time
step = 0
while True:
start, stop = page_size * step, page_size * (step+1)
transactions = sql_session.query(Transaction).slice(start, stop).all()
if transactions is None:
break
for t in transactions:
f.write(str(t))
f.write('n')
if len(transactions) < page_size:
break
step += 1
f.close()
answered Nov 29 '18 at 15:02
William RossWilliam Ross
86321141
Solved by pagination:
page_size = 10000 # get x number of items at a time
step = 0
while True:
start, stop = page_size * step, page_size * (step+1)
transactions = sql_session.query(Transaction).slice(start, stop).all()
if transactions is None:
break
for t in transactions:
f.write(str(t))
f.write('n')
if len(transactions) < page_size:
break
step += 1
f.close()
answered Nov 29 '18 at 15:02
William RossWilliam Ross
86321141
answered Nov 29 '18 at 15:02
William RossWilliam Ross
86321141
answered Nov 29 '18 at 15:02
William RossWilliam Ross
86321141
answered Nov 29 '18 at 15:02
William RossWilliam Ross
86321141
86321141
add a comment |
add a comment |
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1
There is a page in the MySQL docs that might help you with debugging.
– SuperShoot
Nov 23 '18 at 21:21
1
Also this answer covers pagination.
– SuperShoot
Nov 23 '18 at 21:23