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Listing all extras of an Intent
For debugging reasons I want to list all extras (and their values) of an Intent. Now, getting the keys isn't a problem
12 A...
Insert, on duplicate update in PostgreSQL?
...ubject to race conditions that mean it might still fail with duplicate key error if a row is inserted concurrently, or might terminate with no row inserted when a row is deleted concurrently. A SERIALIZABLE transaction on PostgreSQL 9.1 or higher will handle it reliably at the cost of a very high se...
Any way to clear python's IDLE window?
I know there's a similar topic about python console, but I do not know if they are the same. I tried system("clear") and it didn't work here.
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How to prevent form from submitting multiple times from client side?
...urn false and then validation is called. So if my form has some validation error the form never gets submitted!!
– bjan
Jun 8 '12 at 12:09
6
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Hadoop “Unable to load native-hadoop library for your platform” warning
... CentOs . When I run start-dfs.sh or stop-dfs.sh , I get the following error:
21 Answers
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Converting NSString to NSDate (and back again)
...r *detector = [NSDataDetector dataDetectorWithTypes:NSTextCheckingAllTypes error:nil];
[detector enumerateMatchesInString:dateString
options:kNilOptions
range:NSMakeRange(0, [dateString length])
usingBlock:^(NSTextChecki...
Add Foreign Key to existing table
... Do not just run "SET FOREIGN_KEY_CHECKS=0;" if you get the error "a foreign key constraint fails", you obviously have bad data that you must fix or else you will get bigger problems down the line.
– MazeChaZer
Jun 11 '18 at 12:05
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In Python, how do I indicate I'm overriding a method?
...'hello kitty!'
and if you do a faulty version it will raise an assertion error during class loading:
class ConcreteFaultyImplementer(MySuperInterface):
@overrides(MySuperInterface)
def your_method(self):
print 'bye bye!'
>> AssertionError!!!!!!!
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What is the difference between float and double?
...og(10) = 7.22 digits
This precision loss could lead to greater truncation errors being accumulated when repeated calculations are done, e.g.
float a = 1.f / 81;
float b = 0;
for (int i = 0; i < 729; ++ i)
b += a;
printf("%.7g\n", b); // prints 9.000023
while
double a = 1.0 / 81;
double b = ...
Number of occurrences of a character in a string [duplicate]
... the number of occurrences of a certain character such as & in the following string.
6 Answers
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