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How to create relationships in MySQL
In class, we are all 'studying' databases, and everyone is using Access. Bored with this, I am trying to do what the rest of the class is doing, but with raw SQL commands with MySQL instead of using Access.
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Android: ListView elements with multiple clickable buttons
I've a ListView where every element in the list contains a TextView and two different Buttons. Something like this:
8 Ans...
How do you round a number to two decimal places in C#?
...per to specify the type of rounding (Round-to-even or Away-from-zero). The Convert.ToInt32() method and its variations use round-to-even. The Ceiling() and Floor() methods are related.
You can round with custom numeric formatting as well.
Note that Decimal.Round() uses a different method than Mat...
How do DATETIME values work in SQLite?
...ions can chose to store dates and times in any of these formats and freely convert between formats using the built-in date and time functions.
SQLite built-in Date and Time functions can be found here.
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Is it possible to declare two variables of different types in a for loop?
...se a structured binding declaration. The syntax has been supported in gcc and clang for years (since gcc-7 and clang-4.0) (clang live example). This allows us to unpack a tuple like so:
for (auto [i, f, s] = std::tuple{1, 1.0, std::string{"ab"}}; i < N; ++i, f += 1.5) {
// ...
}
The above...
C＋＋模板的特化 - C/C++ - 清泛网 - 专注C/C++及内核技术
...stantiation;
notes: the compiler will use f3 as the instantiation for f1, and use f2 as the specialization for f1;
rule: specialization must be before instantiation (*);
Above we have discuss the template function, and then we'll focus on member template function.
acronym: MTF(member templat...
PHP - iterate on string characters
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Step 1: convert the string to an array using the str_split function
$array = str_split($your_string);
Step 2: loop through the newly created array
foreach ($array as $char) {
echo $char;
}
You can check the PHP docs for more in...
Is it possible to force Excel recognize UTF-8 CSV files automatically?
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I use Notepad++ to easily convert the .csv from UTF-8 to UTF-8 with BOM
– Sébastien
Jun 6 '16 at 8:02
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Is there a C# case insensitive equals operator?
...ore case string comparison. This is also the fastest way, much faster than converting the strings to lower or upper case and comparing them after that.
I tested the performance of both approaches and the ordinal ignore case string comparison was more than 9 times faster! It is also more reliable th...
What is the difference between named and positional parameters in Dart?
Dart supports both named optional parameters and positional optional parameters. What are the differences between the two?
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