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Error Code: 1005. Can't create table '…' (errno: 150)
...when I was trying to deploy an old system that was initially running MySQL 5.0 or similar version, where the default storage engine was MyISAM and the scripts were running OK. My current environment is 5.5 and the default storage is InnoDB. Adding set names 'utf8', storage_engine=MYISAM; at the beg...
Get record counts for all tables in MySQL database
...h, This is one of the restrictions of InnoDB. See dev.mysql.com/doc/refman/5.0/en/innodb-restrictions.html, section Restrictions on InnoDB Tables, for more info. You could always use a SELECT COUNT(*) FROM t, which however, is a lot slower
– Marking
Feb 23 '12 ...
INSERT IF NOT EXISTS ELSE UPDATE?
...NULL, 1, 2, 5);
The "SELECT * FROM data" will give you:
2|2|2|3.0
3|1|2|5.0
Note that the data.id is "3" and not "1" because REPLACE does a DELETE and INSERT, not an UPDATE. This also means that you must ensure that you define all necessary columns or you will get unexpected NULL values.
...
Are Java static initializers thread safe?
...or lazy initialization
enum Singleton {
INSTANCE;
}
or for pre Java 5.0
class Singleton {
static class SingletonHolder {
static final Singleton INSTANCE = new Singleton();
}
public static Singleton instance() {
return SingletonHolder.INSTANCE;
}
}
As the static bloc...
UIImagePickerController error: Snapshotting a view that has not been rendered results in an empty sn
...e with Apple's PhotoPicker sample code project.
I was using Xcode Version 5.0 and iOS 7.0.3 on an iPhone 4.
Steps to Reproduce:
Download Apple's PhotoPicker sample project at
https://developer.apple.com/library/ios/samplecode/PhotoPicker/Introduction/Intro.html
In APLViewController.m comment ou...
How to deal with “java.lang.OutOfMemoryError: Java heap space” error?
...d objects in the memory. After a quick research I found Ergonomics in the 5.0 Java Virtual Machine and others saying on Windows machine the JVM defaults max heap size as 64MB .
...
Why does InetAddress.isReachable return false, when I can ping the IP address?
...onnected" for one IPv4 and one IPv6 address. The bug is also fixed in Java 5.0 b22. Maybe isReachable is more reliable now days.
– Lii
Jan 23 at 15:10
...
Can I change multiplier property for NSLayoutConstraint?
... YES;
[self.view layoutIfNeeded]; // or using [UIView animate ...]
Swift 5.0 version
var standardConstraint: NSLayoutConstraint!
var zoomedConstraint: NSLayoutConstraint!
// ...
// switch between constraints
standardConstraint.isActive = false // this line should always be the first line. becau...
What are the uses of “using” in C#?
...an create aliases for namespaces and types, as pointed out in the book "C# 5.0 In a Nutshell: The Definitive Guide" (http://www.amazon.com/5-0-Nutshell-The-Definitive-Reference-ebook/dp/B008E6I1K8), by Joseph and Ben Albahari. One example:
namespace HelloWorld
{
using AppFunc = Func<IDictio...
Rails 4: how to use $(document).ready() with turbo-links
...heck your Gemfile.lock for the turbolinks version used. If it is less then 5.0 then use page:change or upgrade turbolinks. Also found this, may be relevant to some, where turbolinks translates events to the old event names: github.com/turbolinks/turbolinks/blob/v5.0.0/src/turbolinks/…
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