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xpath find if node exists
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Patrick McDonaldPatrick McDonald
57.9k1313 gold badges9494 silver badges115115 bronze badges
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Self-references in object literals / initializers
...he only thing that I can tell you about are getter:
var foo = {
a: 5,
b: 6,
get c() {
return this.a + this.b;
}
}
console.log(foo.c) // 11
This is a syntactic extension introduced by the ECMAScript 5th Edition Specification, the syntax is supported by most modern bro...
MySQL - Make an existing Field Unique
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ALTER IGNORE TABLE mytbl ADD UNIQUE (columnName);
For MySQL 5.7.4 or later:
ALTER TABLE mytbl ADD UNIQUE (columnName);
As of MySQL 5.7.4, the IGNORE clause for ALTER TABLE is removed and
its use produces an error.
So, make sure to remove duplicate entries first as IGNORE key...
MySQL “Group By” and “Order By”
..., so unless they are the same, the values chosen are indeterminate."
As of 5.7.5 ONLY_FULL_GROUP_BY is enabled by default so non-aggregate columns cause query errors (ER_WRONG_FIELD_WITH_GROUP)
As @mikep points out below the solution is to use ANY_VALUE() from 5.7 and above
See
http://www.cafewebmas...
Cannot find executable for CFBundle CertUIFramework.axbundle
Just updated to Xcode 5 and this is the first error its throwing on the logger for all my apps. Can't seem to understand why this is happening.
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Generic method multiple (OR) type constraint
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answered May 31 '12 at 12:50
Botz3000Botz3000
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How to set Default Controller in asp.net MVC 4 & MVC 5
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Imad Alazani
6,22055 gold badges3030 silver badges5858 bronze badges
answered Jan 20 '13 at 16:30
Dave AlperovichDave A...
How do I generate random integers within a specific range in Java?
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+150
In Java 1.7 or later, the standard way to do this is as follows:
import java.util.concurrent.ThreadLocalRandom;
// nextInt is norma...
Get operating system info
...s that, it sniffs your core operating system model, for example windows nt 5.1 as my own.
It then passes windows nt 5.1/i to Windows XP as the operating system.
Using: '/windows nt 5.1/i' => 'Windows XP', from an array.
You could say guesswork, or an approximation yet nonetheless pretty much ...
Can overridden methods differ in return type?
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public Circle build() {
....
}
This is specified in section 8.4.5 of the Java Language Specification:
Return types may vary among methods that override each other if the return types are reference types. The notion of return-type-substitutability supports covariant returns, that is, t...