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Creating and Update Laravel Eloquent
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There is and it's called firstOrNew / firstsOrCreate
– malhal
Aug 24 '14 at 11:59
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When should I use malloc in C and when don't I?
I understand how malloc() works. My question is, I'll see things like this:
6 Answers
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Is git's semi-secret empty tree object reliable, and why is there not a symbolic name for it?
...0 +0000" GIT_COMMITTER_DATE="Thu, 01 Jan 1970 00:00:00 +0000" git commit --allow-empty -m 'Initial commit'
Will give you:
(See the tree SHA1?)
You can even rebase your existing history on top of that empty commit (see "git: how to insert a commit as the first, shifting all the others?")
In bo...
How do I build a numpy array from a generator?
... lists. This is necessary so that space for each item can be consecutively allocated in memory. Consecutive allocation is the key feature of numpy arrays: this combined with native code implementation let operations on them execute much quicker than regular lists.
Keeping this in mind, it is techni...
Transaction isolation levels relation with locks on table
...B just executes a SELECT statement to read data. C reads and updates data. All these process work on the same table T.
READ UNCOMMITTED - no lock on the table. You can read data in the table while writing on it. This means A writes data (uncommitted) and B can read this uncommitted data and use it...
Naming convention for Scala constants?
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The officially recommended style (and I do mean officially) is the first style, camel case with first letter are upper case. It's laid down clearly by Odersky on Programming in Scala.
The style is also followed by the standard library...
APP INVENTOR硬件交互学习教程04——蓝牙控制继电器 · App Inventor 2 中文网
....2程序逻辑块
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APP INVENTOR硬件交互学习教程05——自动连接蓝牙实现 · App Inventor 2 中文网
...。具体代码请参考下图
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APP INVENTOR硬件交互学习教程08——增加语音播报 · App Inventor 2 中文网
...存，复选框配置模式
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APP INVENTOR硬件交互学习教程09——增加人机交互提示 · App Inventor 2 中文网
...未连接蓝牙时逻辑处理
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