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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
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I would recommend using INSERT...ON DUPLICATE KEY UPDATE.
If you use INSERT IGNORE, then the row won't actually be inserted if it results in a duplicate key. But the statement won't generate an error. It generates a warning instead....
How to find memory leak in a C++ code/project?
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Instructions
Things You'll Need
Proficiency in C++
C++ compiler
Debugger and other investigative software tools
1
Understand the operator basics. The C++ operator new allocates heap memory. The delete operator frees heap memory. For every new, you should use a delete so that y...
What issues should be considered when overriding equals and hashCode in Java?
...you should override the other.
Use the same set of fields that you use to compute equals() to compute hashCode().
Use the excellent helper classes EqualsBuilder and HashCodeBuilder from the Apache Commons Lang library. An example:
public class Person {
private String name;
private int age...
:: (double colon) operator in Java 8
...a lot of syntax for just calling Math.max. That's where lambda expressions come into play. Since Java 8 it is allowed to do the same thing in a much shorter way:
reduce((int left, int right) -> Math.max(left, right));
How does this work? The java compiler "detects", that you want to implement ...
HTML5 dragleave fired when hovering a child element
... OMG this is the most obvious solution and only had ONE vote... Come on people, you can do better. I was thinking about that but after seeing the level of sophistication of the first few answers I almost discarded it. Did you have any drawbacks ?
– Arthur Corenzan
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Phonegap Cordova installation Windows
...e's what i discovered.
Ignore the installation documentation and all the command line, node.js stuff (seriously you will waste hours on this.
Go to github and simply download the PhoneGap master .zip
In that zip are project files for window phone, etc platform... just use those templates.
I don'...
How do I record audio on iPhone with AVAudioRecorder?
...ing KVC.
#define DOCUMENTS_FOLDER [NSHomeDirectory() stringByAppendingPathComponent:@"Documents"]
- (void) startRecording{
UIBarButtonItem *stopButton = [[UIBarButtonItem alloc] initWithTitle:@"Stop" style:UIBarButtonItemStyleBordered target:self action:@selector(stopRecording)];
self.navigatio...
Git push error '[remote rejected] master -> master (branch is currently checked out)'
...e folder contains only the actual repository data).
Execute the following command in your remote repository folder:
git config --bool core.bare true
Then delete all the files except .git in that folder. And then you will be able to perform git push to the remote repository without any errors.
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jQuery animate backgroundColor
...fast. Since a minified version isn't supplied you might like test various compressors and make your own min version. YUI gets the best compression in this case needing only 2317 bytes and since it is so small - here it is:
(function (d) {
d.each(["backgroundColor", "borderBottomColor", "borde...
Naming returned columns in Pandas aggregate function? [duplicate]
...f.columns.ravel()]
For example:
import pandas as pd
import pandas.rpy.common as com
import numpy as np
data = com.load_data('Loblolly')
print(data.head())
# height age Seed
# 1 4.51 3 301
# 15 10.89 5 301
# 29 28.72 10 301
# 43 41.74 15 301
# 57 52.70 20 301
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