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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...
Is there a Python equivalent to Ruby's string interpolation?
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@Caste see here: docs.python.org/library/stdtypes.html#string-formatting and post a follow up comment if you need any more details
– mikej
Dec 15 '10 at 13:59
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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.
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What is a raw type and why shouldn't we use it?
... String name = (String) o;
System.out.println(name);
} // throws ClassCastException!
// java.lang.Boolean cannot be cast to java.lang.String
Now we run into trouble at run-time, because names contains something that isn't an instanceof String.
Presumably, if you want names to contain only...
Cannot create an array of LinkedLists in Java…?
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For some reason you have to cast the type and make the declaration like this:
myMatrix = (LinkedList<IntegerNode>[]) new LinkedList<?>[numRows];
share
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How to do ToString for a possibly null object?
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C# 6.0 Edit:
With C# 6.0 we can now have a succinct, cast-free version of the orignal method:
string s = myObj?.ToString() ?? "";
Or even using interpolation:
string s = $"{myObj}";
Original Answer:
string s = (myObj ?? String.Empty).ToString();
or
string s = (myObjc ?? "")....
What are POD types in C++?
...en pointers to vtables, offsets that get applied to the address when it is cast to other types (at least if the target's POD too), constructors, or destructors. Roughly speaking, a type is a POD when the only things in it are built-in types and combinations of them. The result is something that "act...
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 ...
What are the differences between “generic” types in C++ and Java?
...acro). In Java they are basically syntactic sugar to minimize boilerplate casting of Objects. Here is a pretty decent introduction to C++ templates vs Java generics.
To elaborate on this point: when you use a C++ template, you're basically creating another copy of the code, just as if you used a ...
How do I enumerate through a JObject?
...asons I don't understand, you can't use it with Linq unless you explicitly cast to the enumerable type. I.e. you ((IEnumerable<KeyValuePair<string, JToken>>)obj).Select(...) instead of plain-old obj.Select(...); or at least that's what I found it one part of my code.
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