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Ways to save enums in database
...ues. For example, changing the Suit enumeration to:
public enum Suit { Unknown, Heart, Club, Diamond, Spade }
would have to become :
public enum Suit {
Unknown = 4,
Heart = 1,
Club = 3,
Diamond = 2,
Spade = 0 }
in order to maintain the legacy numerical values sto...
Get records with max value for each group of grouped SQL results
...wers would do)
Note: This is a mysql-only solution. All other databases I know will throw an SQL syntax error with the message "non aggregated columns are not listed in the group by clause" or similar. Because this solution uses undocumented behavior, the more cautious may want to include a test to ...
How can I make a JPA OneToOne relation lazy
...t bytecode instrumentation. The reason for this is that owner entity MUST know whether association property should contain a proxy object or NULL and it can't determine that by looking at its base table's columns due to one-to-one normally being mapped via shared PK, so it has to be eagerly fetched ...
How to hide “Showing 1 of N Entries” with the dataTables.js library
...
Now, this seems to work:
$('#example').DataTable({
"info": false
});
it hides that div, altogether
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How to avoid merge-commit hell on GitHub/BitBucket
... This is a great answer. I use rebase as often as possible. I didn't know about the --ff-only flag though. Pretty cool!
– Leo Correa
May 3 '13 at 12:24
3
...
Polymorphism vs Overriding vs Overloading
... public void goPee(){
System.out.println("Sit Down");
}
}
Now we can tell an entire room full of Humans to go pee.
public static void main(String[] args){
ArrayList<Human> group = new ArrayList<Human>();
group.add(new Male());
group.add(new Female());
//...
Is there any difference between GROUP BY and DISTINCT
...s.
For example, if you have a bunch of purchase records, and you want to know how much was spent by each department, you might do something like:
SELECT department, SUM(amount) FROM purchases GROUP BY department
This will give you one row per department, containing the department name and the su...
Find the most common element in a list
...e highest frequency item (for just 1 item, that's O(N) time). As Counter() now is heavily optimised (counting takes place in a C loop), it can easily beat this solution even for small lists. It blows it out of the water for large lists.
– Martijn Pieters♦
Oct...
Clear form field after select for jQuery UI Autocomplete
...
Fantastic! I feel silly though. Now I know, and knowing is half the battle.
– Jon F Hancock
Apr 1 '10 at 16:29
...
regex for zip-code
...
@ProVega: Reading the comments on the (now deleted) answer you linked to, that appears to be incorrect. For example, 00544 is a valid zip code; 544 is not.
– Keith Thompson
Dec 5 '14 at 20:59
...