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How do I update if exists, insert if not (AKA “upsert” or “merge”) in MySQL?
...
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 TIMESTAMP NOT NULL DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
PRIMARY KEY (id)
);
mysql> REPLACE INTO test VALUES (1, '...
Can enums be subclassed to add new elements?
...ed in this topic. But I'll add the mechanics to the discussion.
Here is a test enum:
public enum TEST {
ONE, TWO, THREE;
}
The resulting code from javap:
public final class TEST extends java.lang.Enum<TEST> {
public static final TEST ONE;
public static final TEST TWO;
public s...
Set transparent background using ImageMagick and commandline prompt
...ck 6.6.9-7 on Ubuntu 12.04.
What worked for me was the following:
convert test.png -transparent white transparent.png
That changed all the white in the test.png to transparent.
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How do I get started with Node.js [closed]
...n for your text editor that will automatically run it on your code.
Unit Testing:
Mocha is a popular test framework.
Vows is a fantastic take on asynchronous testing, albeit somewhat stale.
Expresso is a more traditional unit testing framework.
node-unit is another relatively traditional unit te...
What's the easy way to auto create non existing dir in ansible
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According to the documentation (and my tests), the subdirectories are always created, and recurse=yes only applies permissions recursively. However, the documentation states that this happens automatically since v1.7, so recurse might well be obsolete.
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Checking if a key exists in a JavaScript object?
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Checking for undefined-ness is not an accurate way of testing whether a key exists. What if the key exists but the value is actually undefined?
var obj = { key: undefined };
obj["key"] !== undefined // false, but the key exists!
You should instead use the in operator:
"key" ...
PHP json_encode encoding numbers as strings
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I've done a very quick test :
$a = array(
'id' => 152,
'another' => 'test',
'ananother' => 456,
);
$json = json_encode($a);
echo $json;
This seems to be like what you describe, if I'm not mistaken ?
And I'm getting as outpu...
PHP random string generator
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+1 for the shortest answer :). But not the best answer for every use-case. This code will output strings where each character won't appear more than once (thus making it weaker for brute force attacks) and won't output anything longer than ...
How to change MySQL column definition?
I have a mySQL table called test:
3 Answers
3
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How to export JavaScript array info to csv (on client side)?
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Based on the answers above I created this function that I have tested on IE 11, Chrome 36 and Firefox 29
function exportToCsv(filename, rows) {
var processRow = function (row) {
var finalVal = '';
for (var j = 0; j < row.length; j++) {
var innerValue ...