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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 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...
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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...
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...
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...
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...
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...
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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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.
...