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How do I get the MIN() of two fields in Postgres?
...alue from a list of any number of expressions. The expressions must all be convertible to a common data type, which will be the type of the result (see Section 10.5 for details). NULL values in the list are ignored. The result will be NULL only if all the expressions evaluate to NULL.
Note that...
NSLog the method name with Objective-C in iPhone
... Method calls like [self doSomething:arg1 somethingElse:arg2] get converted into the C function call objc_msgSend(self, "doSomething:somethingElse:, arg1, arg2);. The second parameter of objc_msgSend() takes a char*. Remember that because the Objective-C runtime is dynamic, it's actually us...
Validating IPv4 addresses with regexp
...t also leads to difficulties with verification/security as 023 needs to be converted to 23 to avoid duplicates, etc. Thanks for trying to make things better !
– Danail Gabenski
Dec 27 '19 at 1:03
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How to implement onBackPressed() in Fragments?
...ddToBackStack before commit:
@Override
public void onBackPressed() {
int count = getSupportFragmentManager().getBackStackEntryCount();
if (count == 0) {
super.onBackPressed();
//additional code
} else {
getSupportFragmentManager().popBackStack();
}
}
...
Multiple “order by” in LINQ
...gone all this time without knowing about ThenBy?! (Edit: looks like it was introduced in .NET 4.0, which explains how it slipped past me unnoticed.)
– Jordan Gray
Nov 21 '13 at 15:05
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How to check for an undefined or null variable in JavaScript?
... property doesn't yield an error and simply returns undefined, which, when converted to a boolean, evaluates to false. So, if you don't care about
0 and false, using if(obj.undefProp) is ok. There's a common idiom based on this fact:
value = obj.prop || defaultValue
which means "if obj has the p...
MySQL “incorrect string value” error when save unicode string in Django
...
results = cursor.fetchall()
for row in results:
sql = "ALTER TABLE `%s` convert to character set DEFAULT COLLATE DEFAULT" % (row[0])
cursor.execute(sql)
db.close()
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Differences between C++ string == and compare()?
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std::string::compare() returns an int:
equal to zero if s and t are equal,
less than zero if s is less than t,
greater than zero if s is greater than t.
If you want your first code snippet to be equivalent to the second one, it should actually read:
if (...
How do you produce a .d.ts “typings” definition file from an existing JavaScript library?
...ucco-and-Luke-Hoban-Inside-TypeScript at 00:33:52 they had built a tool to convert WebIDL and WinRT metadata into TypeScript d.ts
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How to use a variable for a key in a JavaScript object literal?
... 'theTop' : 10 }
The PropertyName theTop is an IdentifierName, so it gets converted to the 'theTop' string value, which is the string value of 'theTop'.
It is not possible to write object initializers (literals) with variable keys.
The only three options are IdentifierName (expands to string liter...