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M_PI works with math.h but not with cmath in Visual Studio
... so that you can include it again with that define now changed to add M_PI etc. This is NOT the case with cmath. So you need to make sure you #define _USE_MATH_DEFINES before you include anything else. Hope that clears it up for you :)
Failing that just include math.h you are using non-standard C/...
Cannot resolve the collation conflict between “SQL_Latin1_General_CP1_CI_AS” and “Latin1_General_CI_
...o fields are used together in other places (comparisons, unions, coalesce, etc...) make sure that each of those also have the collation specified.
– Zarepheth
Feb 17 '14 at 21:26
6...
MySQL, Check if a column exists in a table with SQL
...ve to wrap the whole thing in a procedure which allows statements like IF, etc. See stackoverflow.com/questions/7384711/… for an example of how to wrap a procedure around the test for the column and the conditional DML statement.
– Christopher Schultz
Jul 23 ...
Exception messages in English?
...n't reflect the real count (100 in English, 77 in Chinese, 80 in Korean... etc)
– Artemious
Sep 24 '17 at 10:31
I reme...
Flask-SQLAlchemy import/context issue
...__)
db.init_app(app)
app.register_blueprint(reporting)
Note: this is a sketch of some of the power this gives you - there is obviously quite a bit more that you can do to make development even easier (using a create_app pattern, auto-registering blueprints in certain folders, etc.)
...
What does “#define _GNU_SOURCE” imply?
...you sometimes need for implementing system utilities like mount, ifconfig, etc.
broken behavior for lots of POSIX-specified functions, where the GNU folks disagreed with the standards committee on how the functions should behave and decided to do their own thing.
As long as you're aware of these t...
How to unit test an object with database queries
...all a method on, in the sense that they have the same properties, methods, etc. available to caller. But instead of performing whatever action they are programmed to do when a particular method is called, it skips that altogether, and just returns a result. That result is typically defined by you a...
How to install JSTL? The absolute uri: http://java.sun.com/jstl/core cannot be resolved
...ase you're actually using a normal Java EE server such as WildFly, Payara, etc instead of a barebones servletcontainer such as Tomcat, Jetty, etc, then you don't need to explicitly install JSTL at all. Normal Java EE servers already provide JSTL out the box. In other words, you don't need to add JST...
Inserting a tab character into text using C#
...I should capture several values and build a text with them: Name , Age , etc.
9 Answers
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What are file descriptors, explained in simple terms?
...e directly with the kernel, using system calls to read(), write(), close() etc. the handle you use is a file descriptor.
There is a layer of abstraction overlaid on the system calls, which is the stdio interface. This provides more functionality/features than the basic system calls do. For this int...