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Flask SQLAlchemy query, specify column names
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An example here:
movies = Movie.query.filter(Movie.rating != 0).order_by(desc(Movie.rating)).all()
I query the db for movies with rating <> 0, and then I order them by rating with the higest rating first.
Take a look here: Select, Insert, Delete in Flask-SQLAlchemy
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How to set up a cron job to run an executable every hour?
... you're using Ubuntu, you can put a shell script in one of these folders: /etc/cron.daily, /etc/cron.hourly, /etc/cron.monthly or /etc/cron.weekly.
For more detail, check out this post: https://askubuntu.com/questions/2368/how-do-i-set-up-a-cron-job
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Entity Framework select distinct name
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In order to avoid ORDER BY items must appear in the select list if SELECT DISTINCT error, the best should be
var results = (
from ta in DBContext.TestAddresses
select ta.Name
)
.Distinct()
.OrderBy( x => 1);
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Size of Matrix OpenCV
...e, here 2 for z axis, 3 for y axis, 4 for x axis.
By x, y, z, it means the order of the dimensions. x index changes the fastest.
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How is the undo tree used in Vim?
...rse all of the nodes in the tree in chronological or reverse-chronological order (which can be a bit confusing, because it can jump arbitrarily between undo branches, but if you do g- long enough you'll always get where you need to go eventually). :earlier and :later take a time descriptor like 7m ...
Is there a way to access an iteration-counter in Java's for-each loop?
...t variant of for iterates over) even have an index, or even have a defined order (some collections may change the order when you add or remove elements).
See for example, the following code:
import java.util.*;
public class TestApp {
public static void AddAndDump(AbstractSet<String> set, ...
Why are dashes preferred for CSS selectors / HTML attributes?
...ff you do with JavaScript these days, you'd want to use CSS Selectors for fetching elements from the DOM anyway, which makes the whole dot notation rather useless. Which one would you prefer?
var firstName = $('#first-name');
var firstName = document.querySelector('#first-name');
var firstName = do...
How to get last key in an array?
...a numerical array, keep in mind that numerical arrays do not have to go in order, or use all the numbers. This will work if you do not explicitly assign to numeric values, but if you do $a[1] = 1; $a[5] = 5; $a[0] = 0; Then you will have an array with keys (1, 5, 0), in that order. count($a) will ...
Are tuples more efficient than lists in Python?
... lists, moving this structure to tuples decreased lookup times by multiple orders of magnitude for multiple lookups. I believe this to be due to the greater cache locality of the tuple once you start using the tuple due to the removal of the second layer of indirection you demonstrate.
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Why is it not advisable to have the database and web server on the same machine?
...xtra cost, dedicated network connection between the two, more maintenance, etc.), especially for a small application, where neither piece is using too much CPU or memory? Even with two servers, with one server compromised, an attacker could still do serious damage, either by deleting the database, ...
