大约有 40,000 项符合查询结果（耗时：0.0383秒） [XML]
DISTINCT for only one column
...ProductModel,
ROW_NUMBER() OVER(PARTITION BY Email ORDER BY ID DESC) rn
FROM Products
) a
WHERE rn = 1
EDIT:
Example using a where clause:
SELECT *
FROM (
SELECT ID,
Email,
...
Sorting multiple keys with Unix sort
... @Arun POS is explained at the end of the man page. You just append the ordering options to the field number like this: sort -k 3,3nr -k 2,2
– andras
Aug 4 '17 at 15:03
1
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What does 'super' do in Python?
...om the parent class that follows Child in the instance's Method Resolution Order (MRO).
If the instance is a subclass of Child, there may be a different parent that comes next in the MRO.
Explained simply
When you write a class, you want other classes to be able to use it. super() makes it easi...
Exception thrown in NSOrderedSet generated accessors
... implementation of the add object setter to append correctly to a NSMutableOrderedSet.
- (void)addSubitemsObject:(SubItem *)value {
NSMutableOrderedSet* tempSet = [NSMutableOrderedSet orderedSetWithOrderedSet:self.subitems];
[tempSet addObject:value];
self.subitems = tempSet;
}
Reassi...
Removing duplicates in lists
...n approach to get a unique collection of items is to use a set. Sets are unordered collections of distinct objects. To create a set from any iterable, you can simply pass it to the built-in set() function. If you later need a real list again, you can similarly pass the set to the list() function.
T...
Simulating group_concat MySQL function in Microsoft SQL Server 2005?
... WHERE empName = a.empName
ORDER BY empName FOR xml path('')), ' ', REQUIRED SEPERATOR)
FROM project_members a
WHERE empName IS NOT NULL
GROUP BY empName
share
...
How do I get the key at a specific index from a Dictionary in Swift?
...Dictionary.keys)[0] // or .first
Remember, dictionaries are inherently unordered, so don't expect the key at a given index to always be the same.
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Getting an object from an NSSet
... to get a member (not random), or convert it to an array (in no particular order) with allObjects.
A set is appropriate when you don't want duplicates, don't care about order, and want fast membership testing.
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...
Change priorityQueue to max priorityqueue
...ue<Integer> queue = new PriorityQueue<>(10, Collections.reverseOrder());
queue.offer(1);
queue.offer(2);
queue.offer(3);
//...
Integer val = null;
while( (val = queue.poll()) != null) {
System.out.println(val);
}
The Collections.reverseOrder() provides a Comparator that would sort...
How to ignore HTML element from tabindex?
...
If these are elements naturally in the tab order like buttons and anchors, removing them from the tab order with tabindex=-1 is kind of an accessibility smell. If they're providing duplicate functionality removing them from the tab order is ok, and consider adding ari...