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Why doesn't java.util.Set have get(int index)?
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Because sets have no ordering. Some implementations do (particularly those implementing the java.util.SortedSet interface), but that is not a general property of sets.
If you're trying to use sets this way, you should consider using a list inste...
Using LIMIT within GROUP BY to get N results per group?
...gregated function to get all years into a single column, grouped by id and ordered by rate:
SELECT id, GROUP_CONCAT(year ORDER BY rate DESC) grouped_year
FROM yourtable
GROUP BY id
Result:
-----------------------------------------------------------
| ID | GROUPED_YEAR ...
LINQ order by null column where order is ascending and nulls should be last
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Try putting both columns in the same orderby.
orderby p.LowestPrice.HasValue descending, p.LowestPrice
Otherwise each orderby is a separate operation on the collection re-ordering it each time.
This should order the ones with a value first, "then" the order...
The order of elements in Dictionary
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The order of elements in a dictionary is non-deterministic. The notion of order simply is not defined for hashtables. So don't rely on enumerating in the same order as elements were added to the dictionary. That's not guaranteed....
How to run test methods in specific order in JUnit4?
I want to execute test methods which are annotated by @Test in specific order.
18 Answers
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How to request a random row in SQL?
...rom that link):
Select a random row with MySQL:
SELECT column FROM table
ORDER BY RAND()
LIMIT 1
Select a random row with PostgreSQL:
SELECT column FROM table
ORDER BY RANDOM()
LIMIT 1
Select a random row with Microsoft SQL Server:
SELECT TOP 1 column FROM table
ORDER BY NEWID()
Select a r...
Is there a “previous sibling” selector?
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Consider the order property of flex and grid layouts.
I'll focus on flexbox in the examples below, but the same concepts apply to Grid.
With flexbox, a previous sibling selector can be simulated.
In particular, the flex order propert...
How to use Oracle ORDER BY and ROWNUM correctly?
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The where statement gets executed before the order by. So, your desired query is saying "take the first row and then order it by t_stamp desc". And that is not what you intend.
The subquery method is the proper method for doing this in Oracle.
If you want a version ...
Include headers when using SELECT INTO OUTFILE?
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But it will not work if there is an ORDER BY in the SELECT clause. The header line can be anywhere in the generated file depending on the order.
– COil
May 19 '14 at 14:29
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What is “the inverse side of the association” in a bidirectional JPA OneToMany/ManyToOne association
...o understand this, you must take a step back. In OO, the customer owns the orders (orders are a list in the customer object). There can't be an order without a customer. So the customer seems to be the owner of the orders.
But in the SQL world, one item will actually contain a pointer to the other....