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Why can a function modify some arguments as perceived by the caller, but not others?
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Some answers contain the word "copy" in a context of a function call. I find it confusing.
Python doesn't copy objects you pass during a function call ever.
Function parameters are names. When you call a function Python binds these parameters to whatever objects you pass (via names in a ...
Update a column value, replacing part of a string
... clause optimizes the query to only modify the rows with certain URL. Logically, the result will be the same, but the addition of WHERE will make the operation faster.
– Dmytro Shevchenko
Aug 14 '15 at 14:34
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Oracle Differences between NVL and Coalesce
...ented differently.
NVL always evaluates both arguments, while COALESCE usually stops evaluation whenever it finds the first non-NULL (there are some exceptions, such as sequence NEXTVAL):
SELECT SUM(val)
FROM (
SELECT NVL(1, LENGTH(RAWTOHEX(SYS_GUID()))) AS val
FROM dual
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psycopg2: insert multiple rows with one query
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My inserts didn't get registered properly until I called connection.commit() after the execute_values(...).
– Philipp
Aug 18 at 15:24
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.aspx vs .ashx MAIN difference
...and .ashx pages?
I use ashx now when I need to handle a request that was called from code and returned with a response, but I would like a more technical answer please.
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Using async/await for multiple tasks
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int[] ids = new[] { 1, 2, 3, 4, 5 };
Parallel.ForEach(ids, i => DoSomething(1, i, blogClient).Wait());
Although you run the operations in parallel with the above code, this code blocks each thread that each operation runs on. For example, if the network call t...
How to put a unicode character in XAML?
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Markup files that are created in Microsoft Visual Studio are
automatically saved in the Unicode UTF-8 file format, which means that
most special characters, such as accent marks, are encoded correctly.
However, there is a set of commonly-used special characters that are
handled differentl...
Use of ~ (tilde) in R programming Language
...".
The myFormula <- part of that line stores the formula in an object called myFormula so you can use it in other parts of your R code.
Other common uses of formula objects in R
The lattice package uses them to specify the variables to plot.
The ggplot2 package uses them to specify panels fo...
Token Authentication vs. Cookies
...tuations. Ember.js, however, deals also with these issues for you; specifically ember-data is built with this in mind. In conclusion, Ember.js is a framework designed for stateful clients.
Ember.js does not work like a typical stateless web app where the session, the state and the corresponding cook...
What is a domain specific language? Anybody using it? And in what way?
... Groovy is a scripting language that runs in a JVM. It's basically intended to be a Java answer to Ruby. It's a general purpose language but it can be used to write DSLs. docs.groovy-lang.org/docs/latest/html/documentation/…
– Charlie Martin
Jul ...