Questions tagged [querying]
516 questions
1
vote
1 answer
Automated scheduling based on availability
The data:
Students which have varying availability at certain timestamps (hourly) throughout the week.
The challenge:
Creating a schedule based on the data above, where a single faculty member can meet with each student once that week, without any…
Michael Eerdekens
- 11
- 2
1
vote
0 answers
Firestore how to query documents chronologically
I understand that unlike Firebase Realtime DB, there isn't a built in method for querying Firestore documents chronologically.
Other than adding a timestamp field to each document, is there another elegant way to achieve that?
Apparently it isn't…
user6097845
- 1,257
- 1
- 15
- 33
1
vote
1 answer
'List object has no attribute' when querying 3 tables in database
I'm running a query and filtering results on 3 tables.
I wrote the function below to perform this query, it looked like this:
def bookshelf():
your_user = db.session.query(User).filter_by(email=session['email']).first().uid
your_books =…
ARNON
- 1,097
- 1
- 15
- 33
1
vote
2 answers
How to filter an sqlalchemy query to all Parents w/o Children, and all Parents, who fall under conditions in a Flask Form
To begin with, I am very new to coding, so sorry in advance if it is not worth attention.
I work with one to many relationship. Let's say I have a Parent class and a Child class defined as follows:
class Parent(db.Model):
__tablename__ =…
Uladzimir Treihis
- 23
- 6
1
vote
2 answers
Compare Two Tables on Snowflake Where it Contains NULL Values
Hello everyone i am facing an issue, i.e
Table T1 with schema
ID
TYPE
MODEL_ID
FREQ
1
Car
234
5
2
SUV
12
6
3
EV
NULL
NULL
4
HV
NULL
NULL
TABLE T2 with schema and…
The_Third_Eye
- 303
- 3
- 15
1
vote
1 answer
Firebase Firestore: How to update or access and update a field value, in a map, in an array, in a document, that is in a collection
Sorry for the long title. Visually and more precise, I would like to update the stock value after a payment is made. However, I get stuck after querying the entire document (e.g. the selected one with title sneakers). Is there a way to actually…
Stino
- 21
- 2
1
vote
2 answers
SQL Query Error: "sub-select returns 2 columns - expected 1" when trying to match either of two columns of subquery
When I write the following query:
SELECT name
FROM people
WHERE phone_number IN
(SELECT caller, receiver FROM phone_calls WHERE month = 7 AND day = 28 AND year = 2020 AND duration < 60);
I get the following error: sub-select returns 2 columns -…
BroCode
- 11
- 5
1
vote
2 answers
Querying PostgreSQL JSONB column with varying types for data
As part of my schema in my PostgreSQL DB, currently running version 11, but willing to upgrade if it unblocks: I have a jsonb column data, which contains nested objects of various structure across the rows, which I don't have control over. Ex:
row 1…
Norrec
- 531
- 4
- 17
1
vote
1 answer
How to make the cell text label a specifc field in a document in a Firestore collection?
So my goal is to make the tableview cells in my dashboard populate with the specific field "event_name" of the documents in my Firestore collection. Here is my code that I came up with by using the Firebase docs.
override func tableView(_ tableView:…
dsonawave
- 137
- 2
- 12
1
vote
1 answer
How to group data by summed amount less than x
Having an issue handling this in sql. Have a table of Check Amounts tied to customers. If I want to give them each unique numbers to be paid with, I cannot figure out how to do that with just an update statement and not going line by line(there is a…
GroGuru
- 13
- 3
1
vote
0 answers
Dynamic query in postgresql - Rolls rates of paydays
I run a query in postgresql to obtain the category of paydays in t+1 (f.e.02-28-2015) of a set of clients on a cut-off date - previous month t (f.e.01-31-2015). The result is satisfactory, however, if I wanted the rolls rate from January 2015 to…
Jean
- 33
- 7
1
vote
1 answer
Like button is working but not changing to Unlike in django
I've been trying to debug this issue for a day together with my expert coder but we were unable to identify the issue here. The like button works perfectly all right and I am able to query the total likes, but the Clap button does not change to…
user14919679
1
vote
1 answer
Creating a like button in django social media network
I'm new to django and I'm trying to create a like button for my blog posts. In my HomeFeed app
However, I received this error when i click on the like button that i have created:
ValueError invalid literal for int() with base 10: 'uien-jdhn-fds'
I…
user14820658
1
vote
1 answer
Django query for matching 'cousin' objects (with same grandparent)
I am trying to write some validations on form input and need to check that the instance being created doesn't already exist under the same grandparent. The field I am validating against isn't a primary key as it can exist outside the 'family'.
I…
fdeboo
- 325
- 1
- 11
1
vote
2 answers
Error on MongoId query with any_of and conditions on a same attribute
When running the following MongoId query
Project.any_of(
{ completed_at: nil}, { :completed_at.gte => @start_date}
)
it produces this error:
"This method is not prepared to handle key being a Key and serializer being not nil"
I found the…
MegaTux
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