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Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?
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After deleting large data, user have to shrink the tables and log files also to reclaim the disk space.
– Muhammad Yousaf Sulahria
Oct 22 '16 at 16:15
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return query based on date
...we do it all in one shot: new Date(new Date().getTime()-60*5*1000)
...then convert to ISO string: .toISOString()
new Date(new Date().getTime()-60*5*1000).toISOString() gives us 2017-01-14T08:53:17.586Z
Of course this is a little easier with variables if you're using the node-mongodb-native driver,...
JS: Check if date is less than 1 hour ago?
... do it as follows:
First find difference of two dates i-e in milliseconds
Convert milliseconds into minutes
If minutes are less than 60, then it means date is within hour else not within hour.
var date = new Date("2020-07-12 11:30:10");
var now = new Date();
var diffInMS = now - date;
var msInHour...
What is the difference between `new Object()` and object literal notation?
...umber"
The object created using the above method (new Object(1)) would be converted to object type if a property is added to it.
var obj = new Object(1);
typeof obj // "number"
obj.a = 2;
typeof obj // "object"
If the object is a copy of a child class of object, we could add the property without ...
Is gettimeofday() guaranteed to be of microsecond resolution?
...the CPU speed from /proc/cpuinfo and divide to get the number of seconds. Converting this to a double is quite handy.
When I run this on my box, I get
11867927879484732
11867927879692217
it took this long to call printf: 207485
Here's the Intel developer's guide that gives tons of detail.
#in...
Checking if a double (or float) is NaN in C++
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According to the IEEE standard, NaN values have the odd property that comparisons involving them are always false. That is, for a float f, f != f will be true only if f is NaN.
Note that, as some comments below have pointed out, not all compilers ...
Get image data url in JavaScript?
...cation here.
If you have this JS loaded (prior to when it's needed), then converting to dataURL is as simple as:
examples
HTML
<img src="/yo.jpg" onload="console.log(this.toDataURL('image/jpeg'))">
JS
console.log(document.getElementById("someImgID").toDataURL());
GPU fingerprinting
I...
Write a program to find 100 largest numbers out of an array of 1 billion numbers
... number in the queue (the head of the queue), remove the head of the queue and add the new number to the queue.
EDIT:
as Dev noted, with a priority queue implemented with a heap, the complexity of insertion to queue is O(logN)
In the worst case you get billionlog2(100) which is better than billion...
Regular expression search replace in Sublime Text 2
... anemic. Specifically, I want to do a replace on groups, so something like converting this text:
6 Answers
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How to determine if a point is in a 2D triangle? [closed]
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In general, the simplest (and quite optimal) algorithm is checking on which side of the half-plane created by the edges the point is.
Here's some high quality info in this topic on GameDev, including performance issues.
And here's some code to get y...