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What would be C++ limitations compared C language? [closed]
..._t) );
To make it compile as C++ you have to write:
foo_t* foo = static_cast<foo_t*>( malloc ( sizeof(foo_t) ) );
which isn't valid C any more. (you could use the C-style cast, it which case it would compile in C, but be shunned by most C++ coding standards, and also by many C programmers...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...s not suffer of performance issues.
Using Option 1 and 2, aka the COLLATE cast approach, can lead to potential bottleneck, cause any index defined on the column will not be used causing a full scan.
Even though I did not try out Option 3, my hunch is that it will suffer the same consequences of op...
What does void mean in C, C++, and C#?
...
Not disagreeing, but an additional use of void is in the "cast to void" trick to suppress warnings for unused values. It's a bit of a stretch since it doesn't really correspond with how the compiler interprets things, but you can interpret that to mean "I'm using this value to do no...
A numeric string as array key in PHP
...
Yes, it is possible by array-casting an stdClass object:
$data = new stdClass;
$data->{"12"} = 37;
$data = (array) $data;
var_dump( $data );
That gives you (up to PHP version 7.1):
array(1) {
["12"]=>
int(37)
}
(Update: My original answe...
Query to list number of records in each table in a database
...
sp_MSForEachTable 'DECLARE @t AS VARCHAR(MAX);
SELECT @t = CAST(COUNT(1) as VARCHAR(MAX))
+ CHAR(9) + CHAR(9) + ''?'' FROM ? ; PRINT @t'
Output:
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How to concatenate columns in a Postgres SELECT?
...n any case.
For non-string data types, you can "fix" the 1st statement by casting at least one argument to text. (Any type can be cast to text):
SELECT a::text || b AS ab FROM foo;
Judging from your own answer, "does not work" was supposed to mean "returns NULL". The result of anything concatena...
What is the list of valid @SuppressWarnings warning names in Java?
...ngs
boxing to suppress warnings relative to boxing/unboxing operations
cast to suppress warnings relative to cast operations
dep-ann to suppress warnings relative to deprecated annotation
deprecation to suppress warnings relative to deprecation
fallthrough to suppress warnings relative to ...
How to convert DateTime to VarChar
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@Atishay "only supported when casting from character data to datetime or smalldatetime". See the footnotes 6 and 7 at docs.microsoft.com/de-de/sql/t-sql/functions/…
– Colin
Sep 4 '17 at 11:15
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Convert base class to derived class [duplicate]
...eturn myBaseClass;
}
Before I was trying this, which gave me a unable to cast error
public MyDerivedClass GetPopulatedDerivedClass()
{
var newDerivedClass = (MyDerivedClass)GetPopulatedBaseClass();
newDerivedClass.UniqueProperty1 = "Some One";
newDerivedClass.UniqueProperty2 = "Some Thi...
Passing a single item as IEnumerable
...f you pass in a list or an array, then an unscrupulous piece of code could cast it and change the contents, leading to odd behaviour in some situations. You could use a read-only collection, but that's likely to involve even more wrapping. I think your solution is as neat as it gets.
...