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Which is fastest? SELECT SQL_CALC_FOUND_ROWS FROM `table`, or SELECT COUNT(*)
...ND_ROWS?
Just a quick summary: Peter says that it depends on your indexes and other factors. Many of the comments to the post seem to say that SQL_CALC_FOUND_ROWS is almost always slower - sometimes up to 10x slower - than running two queries.
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delete map[key] in go?
...ems a poor use of resources though!
Another way is to check for existence and use the value itself:
package main
func main () {
var sessions = map[string] chan int{};
sessions["moo"] = make (chan int);
_, ok := sessions["moo"];
if ok {
delete(sessions, "moo");
}
}
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Abstraction VS Information Hiding VS Encapsulation
Can you tell me what is the difference between abstraction and information hiding in software development?
22 Answers
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Javascript - get array of dates between 2 dates
... @vaibhavkulkarni You can simply reverse the addays() prototype and modify the while loop. In addition, comments are not the place to start up a new question.
– John Hartsock
Aug 11 '15 at 0:40
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How to remove the border highlight on an input text element
...'focused' (currently selected/tabbed into), many browsers (at least Safari and Chrome) will put a blue border around it.
17...
Why does datetime.datetime.utcnow() not contain timezone information?
...dely-available implementation of tzinfo is non-compliant to the supposed standard.
– bobince
Feb 25 '10 at 16:41
5
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JavaFX Application Icon
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Assuming your stage is "stage" and the file is on the filesystem:
stage.getIcons().add(new Image("file:icon.png"));
As per the comment below, if it's wrapped in a containing jar you'll need to use the following approach instead:
stage.getIcons().add(ne...
How to prevent Node.js from exiting while waiting for a callback?
... version, this may not happen til some part of the operation has completed and all the queues might empty before that occurs, allowing node to exit silently.
This is a sneaky bug, that is one that the module developer might not run into during development, as it will occur less often in busy system...
What effect(s) can the virtual keyword have in Entity Framework 4.1 POCO Code First?
...ties virtual. Navigation properties are marked as virtual for lazy loading and scalar properties are marked as virtual for change tracking.
– Ladislav Mrnka
Apr 8 '11 at 18:31
10
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What is the best way to add options to a select from a JavaScript object with jQuery?
...me inside the loop is very wasteful, as is updating the DOM. See points #3 and #6 at artzstudio.com/2009/04/jquery-performance-rules/…
– Patrick
Oct 12 '14 at 7:03
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