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Select n random rows from SQL Server table
...the key scan of values plus the join cost, which on a large table with a small percentage selection should be reasonable.
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How to handle floats and decimal separators with html5 input type number
... has a default value of 1. If you want the input's validation algorithm to allow floating-point values, specify a step accordingly.
For example, I wanted dollar amounts, so I specified a step like this:
<input type="number" name="price"
pattern="[0-9]+([\.,][0-9]+)?" step="0.01"
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Rails Admin vs. ActiveAdmin [closed]
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I vote for rails_admin. I like its looks and the fact that out of the box all the models are available for administration. The history feature is quite useful too.
Any project with Yehuda Katz as a mentor should be a safe bet.
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docker mounting volumes on host
...independent of the container's life cycle. Docker therefore never automatically delete volumes when you remove a container, nor will it "garbage collect" volumes that are no longer referenced by a container." One of these statements must be wrong.
– mc0e
May 6...
What is the difference between const_iterator and non-const iterator in the C++ STL?
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const_iterators don't allow you to change the values that they point to, regular iterators do.
As with all things in C++, always prefer const, unless there's a good reason to use regular iterators (i.e. you want to use the fact that they're not c...
Using only CSS, show div on hover over
...ibling selector, and is the basis of the suckerfish dropdown menu.
HTML5 allows anchor elements to wrap almost anything, so in that case the div element can be made a child of the anchor. Otherwise the principle is the same - use the :hover pseudo-class to change the display property of another el...
sql ORDER BY multiple values in specific order?
...I have a table with a indexed key and a non indexed field.
I need to find all records with a certain value and return the row.
I would like to know if I can order by multiple values.
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Flask SQLAlchemy query, specify column names
... do I specify the column that I want in my query using a model (it selects all columns by default)? I know how to do this with the sqlalchmey session: session.query(self.col1) , but how do I do it with with models? I can't do SomeModel.query() . Is there a way?
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What can you use Python generator functions for?
...in them. I want to know what types of problems that these functions are really good at solving.
16 Answers
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Is HttpClient safe to use concurrently?
In all the examples I can find of usages of HttpClient , it is used for one off calls. But what if I have a persistent client situation, where several requests can be made concurrently? Basically, is it safe to call client.PostAsync on 2 threads at once against the same instance of HttpClient .
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