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How to display unique records from a has_many through relationship?
...ct => "DISTINCT products.*). In the first case, ALL records are fetched and rails removes the duplicates for you. In the later case, only non-duplicate records are fetched from the db so it might offer better performance if you have a large result set.
– mbreining
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How to write a scalable Tcp/Ip based server
... HTTP where there are many short connections, but rather a client connects and stays connected for hours or days or even weeks).
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OO Design in Rails: Where to put stuff
I'm really enjoying Rails (even though I'm generally RESTless), and I enjoy Ruby being very OO. Still, the tendency to make huge ActiveRecord subclasses and huge controllers is quite natural (even if you do use a controller per resource). If you were to create deeper object worlds, where would you p...
How to iterate through a DataTable
....Text = row["ImagePath"].ToString();
}
...assumes the connection is open and the command is set up properly. I also didn't check the syntax, but it should give you the idea.
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How do I convert a Vector of bytes (u8) to a string
I am trying to write simple TCP/IP client in Rust and I need to print out the buffer I got from the server.
3 Answers
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What should I do if the current ASP.NET session is null?
... the HttpApplication.AcquireRequestState event.
Your code runs in an IHttpHandler, that does not specify either the IRequiresSessionState or IReadOnlySessionState interface.
If you only have code in pages, you won't run into this. Most of my ASP .NET code uses Session without checking for null repe...
Does a valid XML file require an XML declaration?
...ere it says it "should" be used -- which means it is recommended, but not mandatory. In XML 1.1, however, the declaration is mandatory. See section 2.8 of the XML 1.1 Recommendation, where it says "MUST" be used. It even goes on to state that if the declaration is absent, that automatically implies ...
Setting transparent images background in IrfanView
I have some PNG images which consist of a black shape and a transparent background.
Unfortunately, IrfanView shows transparent background as black color, so I see just black on black. I've found in Irfan settings that I can change the window's background color, but it changes only around the image, ...
could not resolve host github.com error while cloning remote repository in git
What I did: I have created a remote repository on Github and I am trying to clone the remote repository on my local machine. While cloning I am providing the clone URL & target folder.
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CHECK constraint in MySQL is not working
...e just ignored.
There is a simple alternative
You can create BEFORE INSERT and BEFORE UPDATE triggers which either cause an error or set the field to its default value when the requirements of the data are not met.
Example for BEFORE INSERT working after MySQL 5.5
DELIMITER $$
CREATE TRIGGER `test_b...