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Efficient paging in SQLite with millions of records
...
Please note that you always have to use an ORDER BY clause; otherwise, the order is arbitrary.
To do efficient paging, save the first/last displayed values of the ordered field(s), and continue just after them when displaying the next page:
SELECT *
FROM MyTable
WHE...
HTML5 Canvas 100% Width Height of Viewport?
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In order to make the canvas full screen width and height always, meaning even when the browser is resized, you need to run your draw loop within a function that resizes the canvas to the window.innerHeight and window.innerWidth....
Vertical (rotated) text in HTML table
...enn: Well, yes, VB.NET code depends on VB.NET but you can do the same with PHP or Phyton or Ruby or whater :) By the way, convert it to C# and you can let it run on mono for Linux or Mac or Solaris.
– Stefan Steiger
Sep 2 '13 at 13:56
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What's the purpose of SQL keyword “AS”?
...ProductRetailPrice,
O.Quantity
FROM Products AS P
LEFT OUTER JOIN Orders AS O ON O.ProductID = P.ProductID
WHERE O.OrderID = 123456
Example 3
It's a good practice to use the AS keyword, and very recommended, but it is possible to perform the same query without one (and I do often).
SELE...
MySQL INNER JOIN select only one row from second table
... = (
SELECT id
FROM payments AS p2
WHERE p2.user_id = u.id
ORDER BY date DESC
LIMIT 1
)
Or
SELECT u.*, p.*
FROM users AS u
INNER JOIN payments AS p ON p.user_id = u.id
WHERE NOT EXISTS (
SELECT 1
FROM payments AS p2
WHERE
p2.user_id = p.user_id AND
(p...
Switch statement: must default be the last case?
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The case statements and the default statement can occur in any order in the switch statement. The default clause is an optional clause that is matched if none of the constants in the case statements can be matched.
Good Example :-
switch(5) {
case 1:
echo "1";
break;
case ...
Should developers have administrator permissions on their PC
...machine they are using. Most debugging tools require admin permissions in order to hook into the runtime of the application they are building.
Further, devs frequently download and try new things. Adding additional steps such as needing a network admin to come by and install something for them si...
What is the best way to get all the divisors of a number?
...s about killing performance. Problem two: the divisors are not returned in order.
– Tomasz Gandor
Dec 10 '14 at 14:37
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In Windows Azure: What are web role, worker role and VM role?
...s, with queue messages consumed by all instances).
You can run .NET, Java, php, python, node, ruby, etc. You just need to distribute the appropriate runtime code along with your project code. All languages can make REST calls to the Azure API, and several languages (including those mentioned above) ...
Mapping a function on the values of a map in Clojure
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I like it, but is there any reason for the arguments order (besides the question) ? I was expecting [f m] as in map for some reason.
– nha
Aug 21 '16 at 22:48
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