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“INSERT IGNORE” vs “INSERT … ON DUPLICATE KEY UPDATE”
...th many rows, I want to skip duplicate entries that would otherwise cause failure. After some research, my options appear to be the use of either:
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Need for predictable random generator
...ndomness in small runs of some games is undesirable -- it does seem too unfair for some use cases.
I wrote a simple Shuffle Bag like implementation in Ruby and did some testing. The implementation did this:
If it still seems fair or we haven't reached a threshold of minimum rolls, it returns a...
Difference between add(), replace(), and addToBackStack()
What is the main difference between calling these methods:
9 Answers
9
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How do I view all commits for a specific day?
...rking on a specific day and update my timesheet based on that, but it's a pain in the ass to type in the full date in ISO format so I just do it like this
git log --after=jun9 --before=jun10
and I add --author to only print my commits
git log --since=jun9 --until=jun10 --author=Robert
This pr...
Swift 编程语言入门教程 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...常量定义类似于函数式编程语言中的变量，一次赋值后就无法修改。多多使用有益健康。
一个常量或变量必须与赋值时拥有相同的类型。因此你不用严格定义类型。提供一个值就可以创建常量或变量，并让编译器推断其类型...
Schema for a multilanguage database
... This option is similar to my option nr 1 but better. It is still hard to maintain and requires creating new tables for new languages, so I'd be reluctant to implement it.
– qbeuek
Nov 27 '08 at 10:22
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Solving “Who owns the Zebra” programmatically?
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Here's a solution in Python based on constraint-programming:
from constraint import AllDifferentConstraint, InSetConstraint, Problem
# variables
colors = "blue red green white yellow".split()
nationalities = "Norwegian German Dane Swede English".split()
pet...
App Inventor 2 项目合并工具 AIMerge · App Inventor 2 中文网
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App Inventor 2 项目合并工具 AIMerge
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App Inventor 2 项目合并工具
本文档最初由米尔斯学院（Mills College）的 Kate Feeney 为 AI Classic 编写。该计划在她的论文通...
Which is faster: Stack allocation or Heap allocation
This question may sound fairly elementary, but this is a debate I had with another developer I work with.
23 Answers
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移动前端开发之viewport的深入理解 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...通过window.innerWidth 来获取，但在Android 2, Oprea mini 和 UC 8中无法正确获取。
现在我们已经有两个viewport了：layout viewport 和 visual viewport。但浏览器觉得还不够，因为现在越来越多的网站都会为移动设备进行单独的设计，所...