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Problems querying with python to BigQuery (Python String Format)

I am trying to make a query to BigQuery in order to modify all the values of a row (in python). When I use a simple string to query, I have no problems. Nevertheless, when I introduce the string formatting the query does not work. As follows I'm presenting the same query, but diminishing the number of columns that I am modifying.
I already made the connection to BigQuery, by defining the Client, etc (and works properly).
I tried:
"UPDATE `riscos-dev.survey_test.data-test-bdrn` SET informaci_meteorol_gica = {inf}, risc = {ri} WHERE objectid = {obj_id}".format(inf = df.informaci_meteorol_gica[index], ri = df.risc[index], obj_id = df.objectid[index])
To specify the input values in format:
df.informaci_meteorol_gica[index] = 'Neu' , also a string for df.risc[index] and df.objectid[index] = 3
I am obtaining the following error message:
BadRequest: 400 Braced constructors are not supported at [1:77]

Instead of using format method of string, I propose you another approach with the f string formating in Python :
def build_query():
inf = "'test_inf'"
ri = "'test_ri'"
obj_id = "'test_obj_id'"
return f"UPDATE `riscos-dev.survey_test.data-test-bdrn` SET informaci_meteorol_gica = {inf}, risc = {ri} WHERE objectid = {obj_id}"
if __name__ == '__main__':
query = build_query()
print(query)
The result is :
UPDATE `riscos-dev.survey_test.data-test-bdrn` SET informaci_meteorol_gica = 'test_inf', risc = 'test_ri' WHERE objectid = 'test_obj_id'
I mocked the query params in my example with :
inf = "'test_inf'"
ri = "'test_ri'"
obj_id = "'test_obj_id'"

Use cursor.executemany instead of cursor.execute with tying panda header to sql variables

I have a python script that updates rows in an oracle sql table correctly, however I am using cursor.execute and try/except so if one update fails, it kills the whole run.
I want to be able to have it run through the whole update and just log the error and move onto the next one, which is where cursor.executemany comes in.
https://cx-oracle.readthedocs.io/en/latest/user_guide/batch_statement.html
Here is the script, it works great, except for the all or nothing error approach.
#oracle sql update statement for SHRTCKN
banner_shrtckn_update = """
UPDATE SATURN.SHRTCKN A
SET A.SHRTCKN_COURSE_COMMENT = :course_comment,
A.SHRTCKN_REPEAT_COURSE_IND = :repeat_ind,
A.SHRTCKN_ACTIVITY_DATE = SYSDATE,
A.SHRTCKN_USER_ID = 'STU00940',
A.SHRTCKN_DATA_ORIGIN = 'APPWORX'
WHERE A.SHRTCKN_PIDM = gb_common.f_get_pidm(:id) AND
A.SHRTCKN_TERM_CODE = :term_code AND
A.SHRTCKN_SEQ_NO = :seqno AND
A.SHRTCKN_CRN = :crn AND
A.SHRTCKN_SUBJ_CODE = :subj_code AND
A.SHRTCKN_CRSE_NUMB = :crse_numb
"""
def main():
# get time of run and current year
now = datetime.datetime.now()
year = str(now.year)+"40"
# configure connection strings for banner PROD
db_pass = os.environ['DB_PASSWORD']
dsn = cx_Oracle.makedsn(host='FAKE', port='1521', service_name='TEST.FAKE.BLAH')
try: # initiate banner db connection -- PROD
banner_cnxn = cx_Oracle.connect(user=config.db_test['user'], password = db_pass, dsn=dsn)
writeLog("---- Oracle Connection Made ----")
insertCount = 0
for index, row in df.iterrows():
shrtcknupdate(row,banner_cnxn)
insertCount = insertCount + 1
banner_cnxn.commit()
banner_cnxn.close()
writeLog(str(insertCount)+" rows updated")
except Exception as e:
print("Error: "+str(e))
writeLog("Error: "+str(e))
def writeLog(content):
print(content)
log.write(str(datetime.date.today())+" "+content+"\n")
#define the variable connection between panda/csv and SHRTCKN table
def shrtcknupdate(row, connection):
sql = banner_shrtckn_update
variables = {
'id' : row.Bear_Nbr,
'term_code' : row.Past_Term,
'seqno' : row.Seq_No,
'crn' : row.Past_CRN,
'subj_code' : row.Past_Prefix,
'crse_numb' : row.Past_Number,
'course_comment' : row.Past_Course_Comment,
'repeat_ind' : row.Past_Repeat_Ind
}
cursor = connection.cursor()
cursor.execute(sql, variables)
if __name__ == "__main__":
writeLog("-------- Process Start --------")
main()
writeLog("-------- Process End --------")
The executemany option, I can turn on batcherrors=True
and it will do exactly what I need.
The problem I am running into, is if I get rid of the for loop that runs through the excel/panda dataframe to update the oracle sql rows, which is not needed when doing the update in batch, then how do I attach the column headers to the sql update statement.
If I leave in the for loop, I get this error when using executemany:
Error: parameters should be a list of sequences/dictionaries or an integer specifying the number of times to execute the statement

For named binds, you need to provide a list of dictionaries. This list can be obtained by to_dict(orient='records'):
‘records’ : list like [{column -> value}, … , {column -> value}]
banner_shrtckn_update = """
UPDATE SATURN.SHRTCKN A
SET A.SHRTCKN_COURSE_COMMENT = :Past_Course_Comment,
A.SHRTCKN_REPEAT_COURSE_IND = :Past_Repeat_Ind,
A.SHRTCKN_ACTIVITY_DATE = SYSDATE,
A.SHRTCKN_USER_ID = 'STU00940',
A.SHRTCKN_DATA_ORIGIN = 'APPWORX'
WHERE A.SHRTCKN_PIDM = gb_common.f_get_pidm(:Bear_Nbr) AND
A.SHRTCKN_TERM_CODE = :Past_Term AND
A.SHRTCKN_SEQ_NO = :Seq_No AND
A.SHRTCKN_CRN = :Past_CRN AND
A.SHRTCKN_SUBJ_CODE = :Past_Prefix AND
A.SHRTCKN_CRSE_NUMB = :Past_Number
"""
def main():
# get time of run and current year
now = datetime.datetime.now()
year = str(now.year)+"40"
# configure connection strings for banner PROD
db_pass = os.environ['DB_PASSWORD']
dsn = cx_Oracle.makedsn(host='FAKE', port='1521', service_name='TEST.FAKE.BLAH')
try: # initiate banner db connection -- PROD
banner_cnxn = cx_Oracle.connect(user=config.db_test['user'], password = db_pass, dsn=dsn)
writeLog("---- Oracle Connection Made ----")
# batch execute banner_shrtckn_update
cursor = banner_cnxn.cursor()
data = df[['Bear_Nbr', 'Past_Term', 'Seq_No', 'Past_CRN', 'Past_Prefix', 'Past_Number', 'Past_Course_Comment', 'Past_Repeat_Ind']].to_dict('records')
cursor.executemany(banner_shrtckn_update, data, batcherrors=True)
for error in cursor.getbatcherrors():
writeLog(f"Error {error.message} at row offset {error.offset}")
banner_cnxn.commit()
banner_cnxn.close()
except Exception as e:
print("Error: "+str(e))
writeLog("Error: "+str(e))
This isn't described in detail in the documenation, but you can find an example for named binds in python-cx_Oracle/samples/bind_insert.py.
(Please note that I adjusted the variable names in your sql statement to the dataframe column names to avoid renaming of the columns at creating data.)

I have an Error with python flask cause of an API result (probably cause of my list) and my Database

I use flask, an api and SQLAlchemy with SQLite.
I begin in python and flask and i have problem with the list.
My application work, now i try a news functions.
I need to know if my json informations are in my db.
The function find_current_project_team() get information in the API.
def find_current_project_team():
headers = {"Authorization" : "bearer "+session['token_info']['access_token']}
user = requests.get("https://my.api.com/users/xxxx/", headers = headers)
user = user.json()
ids = [x['id'] for x in user]
return(ids)
I use ids = [x['id'] for x in user] (is the same that) :
ids = []
for x in user:
ids.append(x['id'])
To get ids information. Ids information are id in the api, and i need it.
I have this result :
[2766233, 2766237, 2766256]
I want to check the values ONE by One in my database.
If the values doesn't exist, i want to add it.
If one or all values exists, I want to check and return "impossible sorry, the ids already exists".
For that I write a new function:
def test():
test = find_current_project_team()
for find_team in test:
find_team_db = User.query.filter_by(
login=session['login'], project_session=test
).first()
I have absolutely no idea to how check values one by one.
If someone can help me, thanks you :)
Actually I have this error :
sqlalchemy.exc.InterfaceError: (InterfaceError) Error binding
parameter 1 - probably unsupported type. 'SELECT user.id AS user_id,
user.login AS user_login, user.project_session AS user_project_session
\nFROM user \nWHERE user.login = ? AND user.project_session = ?\n
LIMIT ? OFFSET ?' ('my_tab_login', [2766233, 2766237, 2766256], 1, 0)

It looks to me like you are passing the list directly into the database query:
def test():
test = find_current_project_team()
for find_team in test:
find_team_db = User.query.filter_by(login=session['login'], project_session=test).first()
Instead, you should pass in the ID only:
def test():
test = find_current_project_team()
for find_team in test:
find_team_db = User.query.filter_by(login=session['login'], project_session=find_team).first()
Asides that, I think you can do better with the naming conventions though:
def test():
project_teams = find_current_project_team()
for project_team in project_teams:
project_team_result = User.query.filter_by(login=session['login'], project_session=project_team).first()

All works thanks
My code :
project_teams = find_current_project_team()
for project_team in project_teams:
project_team_result = User.query.filter_by(project_session=project_team).first()
print(project_team_result)
if project_team_result is not None:
print("not none")
else:
project_team_result = User(login=session['login'], project_session=project_team)
db.session.add(project_team_result)
db.session.commit()

Get custom attribute from python ldap query

i succesfully retrive objects that i need from a Python ldap query, the result is like this
[('uid=xxxxxx,ou=People,dc=xxxxxxx,dc=eu', {'departmentcode': ['xxxxx']})], [('uid=xxxxxx,ou=People,dc=xxxxxxx,dc=eu', {'departmentcode': ['xxxxx']})]
But from this result, i need just departmentcode. So, How to acess departmentcode value?

Try:
data = [('uid=xxxxxx,ou=People,dc=xxxxxxx,dc=eu', {'departmentcode': ['xxxxx']})], [('uid=xxxxxx,ou=People,dc=xxxxxxx,dc=eu', {'departmentcode': ['xxxxx']})]
departmentcode = []
for elem in data:
departmentcode.append(elem[0][1]['departmentcode'])

What is an efficient way of inserting thousands of records into an SQLite table using Django?

I have to insert 8000+ records into a SQLite database using Django's ORM. This operation needs to be run as a cronjob about once per minute.
At the moment I'm using a for loop to iterate through all the items and then insert them one by one.
Example:
for item in items:
entry = Entry(a1=item.a1, a2=item.a2)
entry.save()
What is an efficient way of doing this?
Edit: A little comparison between the two insertion methods.
Without commit_manually decorator (11245 records):
nox#noxdevel marinetraffic]$ time python manage.py insrec
real 1m50.288s
user 0m6.710s
sys 0m23.445s
Using commit_manually decorator (11245 records):
[nox#noxdevel marinetraffic]$ time python manage.py insrec
real 0m18.464s
user 0m5.433s
sys 0m10.163s
Note: The test script also does some other operations besides inserting into the database (downloads a ZIP file, extracts an XML file from the ZIP archive, parses the XML file) so the time needed for execution does not necessarily represent the time needed to insert the records.

You want to check out django.db.transaction.commit_manually.
http://docs.djangoproject.com/en/dev/topics/db/transactions/#django-db-transaction-commit-manually
So it would be something like:
from django.db import transaction
#transaction.commit_manually
def viewfunc(request):
...
for item in items:
entry = Entry(a1=item.a1, a2=item.a2)
entry.save()
transaction.commit()
Which will only commit once, instead at each save().
In django 1.3 context managers were introduced.
So now you can use transaction.commit_on_success() in a similar way:
from django.db import transaction
def viewfunc(request):
...
with transaction.commit_on_success():
for item in items:
entry = Entry(a1=item.a1, a2=item.a2)
entry.save()
In django 1.4, bulk_create was added, allowing you to create lists of your model objects and then commit them all at once.
NOTE the save method will not be called when using bulk create.
>>> Entry.objects.bulk_create([
... Entry(headline="Django 1.0 Released"),
... Entry(headline="Django 1.1 Announced"),
... Entry(headline="Breaking: Django is awesome")
... ])
In django 1.6, transaction.atomic was introduced, intended to replace now legacy functions commit_on_success and commit_manually.
from the django documentation on atomic:
atomic is usable both as a decorator:
from django.db import transaction
#transaction.atomic
def viewfunc(request):
# This code executes inside a transaction.
do_stuff()
and as a context manager:
from django.db import transaction
def viewfunc(request):
# This code executes in autocommit mode (Django's default).
do_stuff()
with transaction.atomic():
# This code executes inside a transaction.
do_more_stuff()

Bulk creation is available in Django 1.4:
https://django.readthedocs.io/en/1.4/ref/models/querysets.html#bulk-create

Have a look at this. It's meant for use out-of-the-box with MySQL only, but there are pointers on what to do for other databases.

You might be better off bulk-loading the items - prepare a file and use a bulk load tool. This will be vastly more efficient than 8000 individual inserts.

To answer the question particularly with regard to SQLite, as asked, while I have just now confirmed that bulk_create does provide a tremendous speedup there is a limitation with SQLite: "The default is to create all objects in one batch, except for SQLite where the default is such that at maximum 999 variables per query is used."
The quoted stuff is from the docs--- A-IV provided a link.
What I have to add is that this djangosnippets entry by alpar also seems to be working for me. It's a little wrapper that breaks the big batch that you want to process into smaller batches, managing the 999 variables limit.

You should check out DSE. I wrote DSE to solve these kinds of problems ( massive insert or updates ). Using the django orm is a dead-end, you got to do it in plain SQL and DSE takes care of much of that for you.
Thomas

def order(request):
if request.method=="GET":
cust_name = request.GET.get('cust_name', '')
cust_cont = request.GET.get('cust_cont', '')
pincode = request.GET.get('pincode', '')
city_name = request.GET.get('city_name', '')
state = request.GET.get('state', '')
contry = request.GET.get('contry', '')
gender = request.GET.get('gender', '')
paid_amt = request.GET.get('paid_amt', '')
due_amt = request.GET.get('due_amt', '')
order_date = request.GET.get('order_date', '')
print(order_date)
prod_name = request.GET.getlist('prod_name[]', '')
prod_qty = request.GET.getlist('prod_qty[]', '')
prod_price = request.GET.getlist('prod_price[]', '')
print(prod_name)
print(prod_qty)
print(prod_price)
# insert customer information into customer table
try:
# Insert Data into customer table
cust_tab = Customer(customer_name=cust_name, customer_contact=cust_cont, gender=gender, city_name=city_name, pincode=pincode, state_name=state, contry_name=contry)
cust_tab.save()
# Retrive Id from customer table
custo_id = Customer.objects.values_list('customer_id').last() #It is return
Tuple as result from Queryset
custo_id = int(custo_id[0]) #It is convert the Tuple in INT
# Insert Data into Order table
order_tab = Orders(order_date=order_date, paid_amt=paid_amt, due_amt=due_amt, customer_id=custo_id)
order_tab.save()
# Insert Data into Products table
# insert multiple data at a one time from djanog using while loop
i=0
while(i<len(prod_name)):
p_n = prod_name[i]
p_q = prod_qty[i]
p_p = prod_price[i]
# this is checking the variable, if variable is null so fill the varable value in database
if p_n != "" and p_q != "" and p_p != "":
prod_tab = Products(product_name=p_n, product_qty=p_q, product_price=p_p, customer_id=custo_id)
prod_tab.save()
i=i+1

I recommend using plain SQL (not ORM) you can insert multiple rows with a single insert:
insert into A select from B;
The select from B portion of your sql could be as complicated as you want it to get as long as the results match the columns in table A and there are no constraint conflicts.

def order(request):
if request.method=="GET":
# get the value from html page
cust_name = request.GET.get('cust_name', '')
cust_cont = request.GET.get('cust_cont', '')
pincode = request.GET.get('pincode', '')
city_name = request.GET.get('city_name', '')
state = request.GET.get('state', '')
contry = request.GET.get('contry', '')
gender = request.GET.get('gender', '')
paid_amt = request.GET.get('paid_amt', '')
due_amt = request.GET.get('due_amt', '')
order_date = request.GET.get('order_date', '')
prod_name = request.GET.getlist('prod_name[]', '')
prod_qty = request.GET.getlist('prod_qty[]', '')
prod_price = request.GET.getlist('prod_price[]', '')
# insert customer information into customer table
try:
# Insert Data into customer table
cust_tab = Customer(customer_name=cust_name, customer_contact=cust_cont, gender=gender, city_name=city_name, pincode=pincode, state_name=state, contry_name=contry)
cust_tab.save()
# Retrive Id from customer table
custo_id = Customer.objects.values_list('customer_id').last() #It is return Tuple as result from Queryset
custo_id = int(custo_id[0]) #It is convert the Tuple in INT
# Insert Data into Order table
order_tab = Orders(order_date=order_date, paid_amt=paid_amt, due_amt=due_amt, customer_id=custo_id)
order_tab.save()
# Insert Data into Products table
# insert multiple data at a one time from djanog using while loop
i=0
while(i<len(prod_name)):
p_n = prod_name[i]
p_q = prod_qty[i]
p_p = prod_price[i]
# this is checking the variable, if variable is null so fill the varable value in database
if p_n != "" and p_q != "" and p_p != "":
prod_tab = Products(product_name=p_n, product_qty=p_q, product_price=p_p, customer_id=custo_id)
prod_tab.save()
i=i+1
return HttpResponse('Your Record Has been Saved')
except Exception as e:
return HttpResponse(e)
return render(request, 'invoice_system/order.html')