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MySQL indexes - what are the best practices?
...mpacts of indexing
UPDATEs and INSERTs will be slower. There's also the extra storage space requirments, but that's usual unimportant these days.
If i have a VARCHAR 2500 column which is searchable from parts of my site, should i index it
No, unless it's UNIQUE (which means it's already ind...
Is 'switch' faster than 'if'?
...ecific questions:
Clang generates one that looks like this:
test_switch(char): # @test_switch(char)
movl %edi, %eax
cmpl $19, %edi
jbe .LBB0_1
retq
.LBB0_1:
jmpq *.LJTI0_0(,%rax,8)
jmp void call<0u>() ...
Getting output of system() calls in Ruby
...tem() at all. The backticks execute the command and return the output as a string. You can then assign the value to a variable like so:
output = `ls`
p output
or
printf output # escapes newline chars
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Remove last character of a StringBuilder?
When you have to loop through a collection and make a string of each data separated by a delimiter, you always end up with an extra delimiter at the end, e.g.
...
How do I disable the “Press ENTER or type command to continue” prompt in Vim?
...
In line with commenter below (who suggested to add extra <CR> at the end of command), when using silent, you can add extra <C-l>, so that you do not have to press it manually. Works with screen well, then.
– Victor Farazdagi
...
What is the difference between static_cast and C style casting?
...For example, the C-style cast would allow an integer pointer to point to a char.
char c = 10; // 1 byte
int *p = (int*)&c; // 4 bytes
Since this results in a 4-byte pointer ( a pointer to 4-byte datatype) pointing to 1 byte of allocated memory, writing to this pointer will either cause ...
How can I pretty-print JSON using Go?
...o turn into JSON. The question also mentions pretty-printing just any JSON string, and that's what I was trying to do. I just wanted to pretty-log some JSON from a POST request (specifically a CSP violation report).
To use MarshalIndent, you would have to Unmarshal that into an object. If you need...
How to add an object to an array
... aData) {
alert(aData[i].fullname());
}
/* convert array of object into string json */
var jsonString = JSON.stringify(aData);
document.write(jsonString);
Push object into array
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Single vs double quotes in JSON
...
JSON syntax is not Python syntax. JSON requires double quotes for its strings.
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Algorithm to return all combinations of k elements from n
... java.util.Arrays;
public class Combination {
public static void main(String[] args){
String[] arr = {"A","B","C","D","E","F"};
combinations2(arr, 3, 0, new String[3]);
}
static void combinations2(String[] arr, int len, int startPosition, String[] result){
if (l...