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How to dynamically compose an OR query filter in Django?
...o:
list = [1, 2, 3]
# it gets a bit more complicated if we want to dynamically build
# OR queries with dynamic/unknown db field keys, let's say with a list
# of db fields that can change like the following
# list_with_strings = ['dbfield1', 'dbfield2', 'dbfield3']
# init our q objects variable to ...
Backbone.js: get current route
... hashchange events or pushState, match the appropriate route, and trigger callbacks. You shouldn't ever have to create one of these yourself — you should use the reference to Backbone.history that will be created for you automatically if you make use of Routers with routes.
[...]"
If you need the...
Why is TypedReference behind the scenes? It's so fast and safe… almost magical!
...ecification, the constructs used to implement them under the hood (vararg calling convention, TypedReference type, arglist, refanytype, mkanyref, and refanyval instructions) are perfectly documented in the CLI Specification (ECMA-335) in the Vararg library.
Being defined in the Vararg Library makes ...
find vs find_by vs where
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Use whichever one you feel suits your needs best.
The find method is usually used to retrieve a row by ID:
Model.find(1)
It's worth noting that find will throw an exception if the item is not found by the attribute that you supply. Use where (as described below, which will return an empty arr...
What's the better (cleaner) way to ignore output in PowerShell? [closed]
...ad and > $null has about a 0.3% overhead.
Addendum 2017-10-16: I originally overlooked another option with Out-Null, the use of the -inputObject parameter. Using this the overhead seems to disappear, however the syntax is different:
Out-Null -inputObject ($(1..1000) | ?{$_ -is [int]})
And no...
Update multiple rows in same query using PostgreSQL
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This is wrong... You will update all rows, even if it is not '123' nor '345'. You should use WHERE column_b IN ('123','456')...
– MatheusOl
Sep 14 '13 at 3:54
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private[this] vs private
...rotected over public doesn't apply.
Use private[this] where performance really matters (since you'll get direct field access instead of methods this way). Otherwise, just settle on one style so people don't need to figure out why this property is private and that one is private[this].
...
Finding the index of elements based on a condition using python list comprehension
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In Python, you wouldn't use indexes for this at all, but just deal with the values—[value for value in a if value > 2]. Usually dealing with indexes means you're not doing something the best way.
If you do need an API similar to Matlab's, you would use numpy, a packag...
Why are Subjects not recommended in .NET Reactive Extensions?
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Ok,
If we ignore my dogmatic ways and ignore "subjects are good/bad" all together. Let us look at the problem space.
I bet you either have 1 of 2 styles of system you need to ingrate to.
The system raises an event or a call back when a message arrives
You need to poll the system to see if t...
CSS table layout: why does table-row not accept a margin?
...ered Jan 2 '10 at 23:42
richardtallentrichardtallent
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