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Why do pthreads’ condition variable functions require a mutex?
...adcast to, one or more of the threads on the waiting list will be woken up and the mutex will be magically locked again for that thread.
You typically see the following operation with condition variables, illustrating how they work. The following example is a worker thread which is given work via a...
SQL Joins Vs SQL Subqueries (Performance)?
...PECT the first query to be quicker, mainly because you have an equivalence and an explicit JOIN. In my experience IN is a very slow operator, since SQL normally evaluates it as a series of WHERE clauses separated by "OR" (WHERE x=Y OR x=Z OR...).
As with ALL THINGS SQL though, your mileage may va...
Making heatmap from pandas DataFrame
I have a dataframe generated from Python's Pandas package. How can I generate heatmap using DataFrame from pandas package.
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How do I add a foreign key to an existing SQLite table?
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SQLite doesn't support the ADD CONSTRAINT variant of the ALTER TABLE command (sqlite.org: SQL Features That SQLite Does Not Implement).
Therefore, the only way to add a foreign key in sqlite 3.6.1 is during CREATE TABLE as follows:
CREATE TABLE child (
id INTEGER PRIMARY KEY,
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Why can templates only be implemented in the header file?
Quote from The C++ standard library: a tutorial and handbook :
17 Answers
17
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html (+css): denoting a preferred place for a line break
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By using
span.avoidwrap { display:inline-block; }
and wrapping the text I want to be kept together in
<span class="avoidwrap"> Text </span>
it will wrap first in preferred blocks and then in smaller fragments as needed.
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Setting up FTP on Amazon Cloud Server [closed]
... to set up FTP on Amazon Cloud Server, but without luck.
I search over net and there is no concrete steps how to do it.
12 ...
Regex to check whether a string contains only numbers [duplicate]
I get false on both "123" and "123f" . I would like to check if the hash only contains numbers. Did I miss something?
21...
When should std::move be used on a function return value? [duplicate]
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met save for the fact that the source object is a function parameter,
and the object to be copied is designated by an lvalue, overload
resolution to select the constructor for the copy is first performed as
if the object were designated by an rvalue.
return foo; is a case of NRVO, so cop...
Pipe output and capture exit status in Bash
I want to execute a long running command in Bash, and both capture its exit status, and tee its output.
15 Answers
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