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MySQL Error 1215: Cannot add foreign key constraint
... I've tried to search for the answer here, but everything I've found has said to either set the db engine to Innodb or to make sure the keys I'm trying to use as a foreign key are primary keys in their own tables. I have done both of these things, if I'm not mistaken. Any other help you guys could...
Which equals operator (== vs ===) should be used in JavaScript comparisons?
...2; //false
This is because the equality operator == does type coercion, meaning that the interpreter implicitly tries to convert the values before comparing.
On the other hand, the identity operator === does not do type coercion, and thus does not convert the values when comparing, and is theref...
Memory management in Qt?
...pendent of the hierarchy of the C++ class hierarchy/inheritance tree. That means, that an assigned child does not need to be a direct subclass of it’s parent. Any (subclass of) QObject will suffice.
There might be some constraints imposed by the constructors for other reasons, however; such as in...
Display back button on action bar
...and then you can custom the back event at onOptionsItemSelected
case android.R.id.home:
this.finish();
return true;
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How do I find the most recent git commit that modified a file?
...o know the last time a file was modified no matter the branch, you can consider all branches by adding the --all option.
– K. C.
Aug 13 '15 at 8:00
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Why Func instead of Predicate?
...> - for the "why?" - one advantage is that "Predicate<T>" is only meaningful if you know what "predicate" means - otherwise you need to look at object-browser (etc) to find the signatute.
Conversely Func<T,bool> follows a standard pattern; I can immediately tell that this is a functi...
Routes with Dash `-` Instead of Underscore `_` in Ruby on Rails
...roller and action.
Also, for creating dynamic urls
map.name_of_route 'id1-:id2-:id3', :controller => 'my_controller', :action => "my_action"
in this case 'id1, id2 & id2 would be passed as http params to the action
In you actions and views,
name_of_route_url(:id1=>val1, :...
CSS: fixed position on x-axis but not y?
...y? So when a user scrolls up, the div tag will scroll up with it, but not side to side?
17 Answers
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Entity Framework and SQL Server View
...tement of your view in another select.
Example:
SELECT
ISNULL(MyPrimaryID,-999) MyPrimaryID,
NULLIF(AnotherProperty,'') AnotherProperty
FROM ( ... ) AS temp
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What is the difference between mocking and spying when using Mockito?
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Don't you mean size() returns 1?
– black
Sep 15 '16 at 14:50
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