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Remove ActiveRecord in Rails 3
...evious comment... in Rails 3.1, it is now --skip-active-record. Notice the extra dash.
– Mark Embling
Sep 3 '11 at 13:56
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show 2 more comme...
Postgresql - change the size of a varchar column to lower length
... other databases, is smart enough to only use just enough space to fit the string (even using compression for longer strings), so even if your column is declared as VARCHAR(255) - if you store 40-character strings in the column, the space usage will be 40 bytes + 1 byte of overhead.
The storage ...
How can you determine a point is between two other points on a line segment?
...
Yes, the extra parenthesis is just a typo. 4 years have passed before someone said something. :)
– Cyrille Ka
Nov 22 '12 at 3:36
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Why does GCC generate 15-20% faster code if I optimize for size instead of speed?
...t z = add(x, y);
sum += z;
}
return sum;
}
int main(int , char* argv[]) {
int result = work(*argv[1], *argv[2]);
return result;
}
and compiled as: g++ -O2 add.cpp main.cpp.
gcc won't inline add()!
That's all, it's that easy to unintendedly create hotspots l...
What is the concept of erasure in generics in Java?
...mpiler generates extra casts where necessary. At execution time, a List<String> and a List<Date> are exactly the same; the extra type information has been erased by the compiler.
Compare this with, say, C#, where the information is retained at execution time, allowing code to contain e...
Sending and Receiving SMS and MMS in Android (pre Kit Kat Android 4.4)
...h an intent for anyone else wondering.
public void sendData(int num){
String fileString = "..."; //put the location of the file here
Intent mmsIntent = new Intent(Intent.ACTION_SEND);
mmsIntent.putExtra("sms_body", "text");
mmsIntent.putExtra("address", num);
mmsIntent.putExtra(...
Generate random numbers using C++11 random library
...;
}
};
thread_local backoff_time_t backoff_time;
int main(int argc, char** argv) {
double x1 = backoff_time.rand();
double x2 = backoff_time.rand();
double x3 = backoff_time.rand();
double x4 = backoff_time.rand();
return 0;
}
~
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How to get the file name from a full path using JavaScript?
...n be used in conjunction with lastIndexOf('/')+1: jsperf.com/replace-vs-substring
– Nate
Aug 3 '14 at 1:39
1
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What is the difference between ArrayList.clear() and ArrayList.removeAll()?
Assuming that arraylist is defined as ArrayList<String> arraylist , is arraylist.removeAll(arraylist) equivalent to arraylist.clear() ?
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What is the maximum length of latitude and longitude? [closed]
...12.3456789), longitude 10 (123.4567890), they both have maximum 7 decimals chars (At least is what i can find in Google Maps),
For example, both columns in Rails and Postgresql looks something like this:
t.decimal :latitude, precision: 9, scale: 7
t.decimal :longitude, precision: 10, scale: 7
...