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How should one use std::optional?
I'm reading the documentation of std::experimental::optional and I have a good idea about what it does, but I don't understand when I should use it or how I should use it. The site doesn't contain any examples as of yet which leaves it harder for me to grasp the true concept of this object. When...
OPTION (RECOMPILE) is Always Faster; Why?
...istics. This can be done by running the following:
EXEC sp_updatestats
And then recreating your execution plan. This will ensure that when your execution plan is created it will be using the latest information.
Adding OPTION(RECOMPILE) rebuilds the execution plan every time that your query exe...
“CASE” statement within “WHERE” clause in SQL Server 2008
...tatements like this:
WHERE (
(LEN('TestPerson') = 0
AND co.personentered = co.personentered
)
OR
(LEN('TestPerson') <> 0
AND co.personentered LIKE '%TestPerson')
)
Although, either way I'm not sure how great of a query plan...
How does “do something OR DIE()” work in PHP?
I'm writing a php app to access a MySQL database, and on a tutorial, it says something of the form
4 Answers
...
Generating v5 UUID. What is name and namespace?
I've read the man page, but I do not undestand what name and namespace are for.
3 Answers
...
What is the meaning of prepended double colon “::”?
...wered Nov 24 '10 at 16:27
Wyatt AndersonWyatt Anderson
8,42811 gold badge1919 silver badges2424 bronze badges
...
Determine if Python is running inside virtualenv
...nside a virtual environment, sys.prefix points to the virtual environment, and sys.base_prefix is the prefix of the system Python the virtualenv was created from.
The above always works for Python 3 stdlib venv and for recent virtualenv (since version 20). Older versions of virtualenv used sys.real_...
Best Practice: Software Versioning [closed]
Is there any guideline or standard best practice how to version a software you develop in your spare time for fun, but nevertheless will be used by some people? I think it's necessary to version such software so that you know about with version one is talking about (e.g. for bug fixing, support, and...
Cookies vs. sessions
...r the sake of creating a login system for my website, I read about cookies and sessions and their differences (cookies are stored in the user's browser and sessions on the server). At that time, I preferred cookies (and who does not like cookies?!) and just said: "who cares? I don't have any good de...
When should we use mutex and when should we use semaphore
When should we use mutex and when should we use semaphore ?
12 Answers
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