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Foreign Key to non-primary key
...a UNIQUE constraint in another table.
So in your case if you make AnotherID unique, it will be allowed. If you can't apply a unique constraint you're out of luck, but this really does make sense if you think about it.
Although, as has been mentioned, if you have a perfectly good primary key as a ...
Nested attributes unpermitted parameters
...hing like
params.require(:person).permit(:name, :age, pets_attributes: [:id, :name, :category])
Some more details can be found in the Ruby edge API docs and strong_parameters on github or here
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Why there can be only one TIMESTAMP column with CURRENT_TIMESTAMP in DEFAULT clause?
...
We can give a default value for the timestamp to avoid this problem.
This post gives a detailed workaround:
http://gusiev.com/2009/04/update-and-create-timestamps-with-mysql/
create table test_table(
id integer not null auto_increment primary key,
stamp_created timestamp ...
How to send a message to a particular client with socket.io
...er. So if user connects from another browser - old connection will be overriden.
– Vladimir Kurijov
Dec 5 '13 at 6:03
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How to remove array element in mongodb?
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Try the following query:
collection.update(
{ _id: id },
{ $pull: { 'contact.phone': { number: '+1786543589455' } } }
);
It will find document with the given _id and remove the phone +1786543589455 from its contact.phone array.
You can use $unset to unset the value i...
Javascript : Send JSON Object with Ajax?
... json_decode(file_get_contents('php://input'));
– David
Oct 22 '17 at 8:28
Dear friends can you share this POST ajax w...
Clean code to printf size_t in C++ (or: Nearest equivalent of C99's %z in C++)
...r for size_t and ptrdiff_t arguments, Visual C++ for instance use %Iu and %Id respectively, I think that gcc will allow you to use %zu and %zd.
You could create a macro:
#if defined(_MSC_VER) || defined(__MINGW32__) //__MINGW32__ should goes before __GNUC__
#define JL_SIZE_T_SPECIFIER "%Iu"
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Checkbox for nullable boolean
...ticking
@model bool?
@Html.CheckBox("", Model.GetValueOrDefault())
inside.
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实现一个简单的服务端推方案 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...便主动通知Nginx，并把相应的标识（比如一个自增的整数ID）保存在Nginx共享内存中，接下来，Nginx不会再去轮询数据库，而是改为轮询本地的共享内存，通过比对标识来判断是否有新消息，如果有便给客户端发出响应。
注：服...
Advantages and disadvantages of GUID / UUID database keys
...ses would have been made a lot easier if all the database keys had been GUID / UUID values. I've considered going down this path a few times, but there's always a bit of uncertainty, especially around performance and un-read-out-over-the-phone-able URLs.
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