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Is there a MySQL option/feature to track history of changes to records?
...ing relatively painless to implement - your existing code doesn't need to know about the triggers and audit stuff.
If the business requirement is "show me what the state of the data was on a given date in the past", it means that the aspect of change over time has entered your solution. Whilst you...
How to get duration, as int milli's and float seconds from ?
...;
typedef std::chrono::duration<float> fsec;
auto t0 = Time::now();
auto t1 = Time::now();
fsec fs = t1 - t0;
ms d = std::chrono::duration_cast<ms>(fs);
std::cout << fs.count() << "s\n";
std::cout << d.count() << "ms\n";
}
which for m...
The import android.support cannot be resolved
...ort Library has been added to your dependencies.
Rebuild your project and now everything should work.
Further reading regarding this Question:
Support Library - Android Dev
Recent Support Library Revisions
Support Library Packages
What is an Android Support Library?
How Android Support Library ...
How to scroll to an element inside a div?
...t_within_div');
var topPos = myElement.offsetTop;
The variable topPos is now set to the distance between the top of the scrolling div and the element you wish to have visible (in pixels).
Now we tell the div to scroll to that position using scrollTop:
document.getElementById('scrolling_div').scr...
Run a callback only if an attribute has changed in Rails
...saving to the database, or within the before_save filter:
changes should now be changes_to_save
changed? should now be has_changes_to_save?
changed should now be changed_attribute_names_to_save
<attribute>_change should now be <attribute>_change_to_be_saved
<attribute>_changed? s...
How to find what code is run by a button or element in Chrome using Developer Tools
...glement of minified code:
(click to zoom)
3. Find the glorious code!
Now, the trick here is to not get carried away pressing the key, and keep an eye out on the screen.
Press the F11 key (Step In) until desired source code appears
Source code finally reached
In the jsFiddle sample provided...
What's the difference between the 'ref' and 'out' keywords?
...
@Deebster you know, that metaphor never did anything to you, why must you torture it so? ;)
– Michael Blackburn
Aug 8 '11 at 16:09
...
Chrome: timeouts/interval suspended in background tabs?
I was testing the accuracy of setTimeout using this test . Now I noticed that (as expected) setTimeout is not very accurate but for most appliances not dramatically inaccurate. Now if I run the test in in Chrome and let it run in a background tab (so, switching to another tab and browse on ther...
Undo a merge by pull request?
Someone accepted a pull request which they shouldn't have. Now we have a bunch of broken code merged in. How do you undo a pull request? I was just going to revert the changes to the commit just before the merge, but I noticed that it merged in a bunch of commits. So now there are all these commits ...
How can I find the length of a number?
...ake its absolute value and adjust the sign afterwards.
Update for ES2015
Now that Math.log10 is a thing, you can simply write
const len = Math.ceil(Math.log10(num + 1));
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