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Control cannot fall through from one case label
...code. But I am getting a "Control cannot fall through from one case label" error.
8 Answers
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must appear in the GROUP BY clause or be used in an aggregate function
...pain is 5 and for canada the best result is 2. It is true, and there is no error.
If we need to display wmname also, we have to answer the question: "What is the RULE to choose wmname from resulting set?" Let's change the input data a bit to clarify the mistake:
cname | wmname | avg ...
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...
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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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...
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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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 = ...
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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