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What is the point of the diamond operator () in Java 7?
... all specific features and have only the Object features except when you'd cast the retrieved object to it's original type which can sometimes be very tricky and result in a ClassCastException.
Using List<String> list = new LinkedList() will get you rawtype warnings.
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Best way to unselect a in jQuery?
What is the best way, using jQuery, to elegantly unselect the option?
15 Answers
15
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How to get multiple counts with one SQL query?
...tion. This is basically the same thing as a PIVOT function in some RDBMS:
SELECT distributor_id,
count(*) AS total,
sum(case when level = 'exec' then 1 else 0 end) AS ExecCount,
sum(case when level = 'personal' then 1 else 0 end) AS PersonalCount
FROM yourtable
GROUP BY distributor_id
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Type of conditional expression cannot be determined because there is no implicit conversion between
...lable database field type, for example a nullable DateTime and you try and cast data to DateTime, when it infact required (DateTime?)
– Mike Upjohn
Sep 16 '15 at 14:58
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Jackson JSON custom serialization for certain fields
... brings this message: Could not write content: java.lang.Integer cannot be cast to java.lang.Float
– Arnie Schwarzvogel
May 19 '18 at 14:54
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What are the relationships between Any, AnyVal, AnyRef, Object and how do they map when used in Java
...or vice versa. This answer stackoverflow.com/questions/2334200/… and its cast to AnyRef just reminded me that this was still mysterious to me.
– huynhjl
Feb 26 '10 at 14:30
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How to filter SQL results in a has-many-through relation
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Results:
Total runtimes from EXPLAIN ANALYZE.
1) Martin 2: 44.594 ms
SELECT s.stud_id, s.name
FROM student s
JOIN student_club sc USING (stud_id)
WHERE sc.club_id IN (30, 50)
GROUP BY 1,2
HAVING COUNT(*) > 1;
2) Erwin 1: 33.217 ms
SELECT s.stud_id, s.name
FROM student s
JOIN ...
How to hide a in a menu with CSS?
...hat Chrome, it seems, will not allow me to hide <option> in a <select> . Firefox will.
13 Answers
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UICollectionView Set number of columns
...ds.width - totalSpace) / CGFloat(numberOfItemsPerRow)) - you should remove casting to Int, because in some cases it make small spaces between cells
– Makalele
Dec 30 '16 at 23:52
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How do you remove all the options of a select box and then add one option and select it with jQuery?
Using core jQuery, how do you remove all the options of a select box, then add one option and select it?
24 Answers
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