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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
...in the table has the same value as a new row for a PRIMARY KEY or a UNIQUE index, the old row is deleted before the new row is inserted.
Note this is not standard SQL. An example from the manual:
CREATE TABLE test (
id INT UNSIGNED NOT NULL AUTO_INCREMENT,
data VARCHAR(64) DEFAULT NULL,
ts...
“Code too large” compilation error in Java
...size for code in Java? I wrote a function with more than 10,000 lines. Actually, each line assigns a value to an array variable.
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_DEBUG vs NDEBUG
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+1. NDEBUG in particular is allowed to be #undef'd and #define'd within a single TU (and reincluding <assert.h> changes the assert macro accordingly). Because this is different than expected/desired, it's common to use another macro to control a ...
Reset other branch to current without a checkout
...-hard to also force the work tree to that content. Or --soft to leave the index alone and only change the branch itself.
– Colin D Bennett
Jun 25 '14 at 19:28
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What is “String args[]”? parameter in main method Java
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args indexing start at 0. (contrary to C giving you the name of the program)
– AdrieanKhisbe
Mar 21 '14 at 10:48
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What is the difference between #include and #include “filename”?
...unix archive), and used the string between the < and > as the key to index into the library.
– Adrian McCarthy
Feb 15 '17 at 23:14
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How do you round a floating point number in Perl?
.... For rounding to a certain number of digits, sprintf() or printf() is usually the easiest
route.
printf("%.3f", 3.1415926535); # prints 3.142
The POSIX module (part of the standard Perl distribution) implements
ceil(), floor(), and a number of other mathematical and trigonometric
func...
C library function to perform sort
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qsort() is the function you're looking for. You call it with a pointer to your array of data, the number of elements in that array, the size of each element and a comparison function.
It does its magic and your array is sorted in-place. An example follows:
#include <st...
ios app maximum memory budget
...ered your own question: try not to go beyond the 70 Mb limit, however it really depends on many things: what iOS version you're using (not SDK), how many applications running in background, what exact memory you're using etc.
Just avoid the instant memory splashes (e.g. you're using 40 Mb of RAM, a...
Replace new lines with a comma delimiter with Notepad++?
... or anything else:
Click Edit -> Blank Operations -> EOL to space
[All the items should now be in a single line separated by a 'space']
Select any 'space' and do a Replace All (by ',')
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