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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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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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RegEx to parse or validate Base64 data
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The simplest solution would be to strip out all whitespace (which is ignored as per the RFC) before validation.
– Ben Blank
Jan 24 '09 at 1:35
2
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Remove a HTML tag but keep the innerHtml
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$('b').contents().unwrap();
This selects all <b> elements, then uses .contents() to target the text content of the <b>, then .unwrap() to remove its parent <b> element.
For the greatest performance, always go native:
var b = document.getElement...
Replacing blank values (white space) with NaN in pandas
I want to find all values in a Pandas dataframe that contain whitespace (any arbitrary amount) and replace those values with NaNs.
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CSS media queries: max-width OR max-height
...iting. It's been a good chance to learn myself! Take the time to systematically read though and I hope it will be helpful.
Media Queries
Media queries essentially are used in web design to create device- or situation-specific browsing experiences; this is done using the @media declaration within...
Append a NumPy array to a NumPy array
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Well, the error message says it all: NumPy arrays do not have an append() method. There's a free function numpy.append() however:
numpy.append(M, a)
This will create a new array instead of mutating M in place. Note that using numpy.append() involves c...
Programmer Puzzle: Encoding a chess board state throughout a game
..., 2 bishops, 1 queen and 1 king as illustrated here:
Positions are generally recorded as a letter for the column followed by the number for the row so White’s queen is at d1. Moves are most often stored in algebraic notation, which is unambiguous and generally only specifies the minimal informa...
Calculate a Running Total in SQL Server
Imagine the following table (called TestTable ):
15 Answers
15
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Get child node index
...ode's index inside of its parent node without iterating over and comparing all children nodes?
11 Answers
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