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SQL/mysql - Select distinct/UNIQUE but return all columns?
...
You're looking for a group by:
select *
from table
group by field1
Which can occasionally be written with a distinct on statement:
select distinct on field1 *
from table
On most platforms, however, neither of the above will work because the behavior o...
fstream默认不支持中文路径和输出整数带逗号的解决办法 - C/C++ - 清泛网 -...
...整数转换为字符串再进行输出，如：
int i = 123456789;
char ch[20];
sprintf((char *)&ch, "%d", i); //整数数据转换为字符数组。
outfile << "i = " << ch << '/n'; //输出不带逗号
上述问题的解决方法有很多，大家可以试试。
fstream 中文路...
How to get rid of punctuation using NLTK tokenizer?
...ample, you can define a tokenizer that picks out sequences of alphanumeric characters as tokens and drops everything else:
from nltk.tokenize import RegexpTokenizer
tokenizer = RegexpTokenizer(r'\w+')
tokenizer.tokenize('Eighty-seven miles to go, yet. Onward!')
Output:
['Eighty', 'seven', 'mil...
Why use static_cast(x) instead of (int)x?
...pointer to a different type, and then dereferencing. Except in the case of character types or certain struct types for which C defines the behavior of this construct, it generally results in undefined behavior in C.
– R.. GitHub STOP HELPING ICE
Feb 4 '12 at 5:...
Why does SIGPIPE exist?
... answered Dec 3 '11 at 17:29
Charlie MartinCharlie Martin
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LINQ equivalent of foreach for IEnumerable
...d evaluating Funcs
var evaluatedObservable = observable.ToEnumerable().Select(func => func()).ToList();
//Win
Assert.That(evaluatedObservable,
Is.EquivalentTo(values.ToList()));
}
The following fails with the error:
Expected: equivalent to < 0, 1, 2, 3, 4, 5, 6, 7, 8, ...
Importance of varchar length in MySQL table
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Anytime your select query uses a temporary table (group and order by operations, among other things) it will convert varchar(200) to a char(200) and performance will suffer.
– Jamie
Feb 7 '13 at 20:1...
Using printf with a non-null terminated string
...rray is null-terminated, it just treats it as a longer array that it's sub-selecting from - which means that if you have a string with nulls in it, this will cause problems.
– lahwran
Mar 16 '16 at 0:39
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How to construct a std::string from a std::vector?
...a quicker/alternative/"better" way to initialize a string from a vector of chars?
7 Answers
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Change MySQL default character set to UTF-8 in my.cnf?
Currently we are using the following commands in PHP to set the character set to UTF-8 in our application.
18 Answers
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