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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 is Full Text Search vs LIKE
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In general, there is a tradeoff between "precision" and "recall". High precision means that fewer irrelevant results are presented (no false positives), while high recall means that fewer relevant results are missing (no false negatives). Using the LIKE operator gives you 100% precisi...
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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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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Calculate a Running Total in SQL Server
Imagine the following table (called TestTable ):
15 Answers
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Create a string with n characters
...o the string.
*/
public String spaces( int spaces ) {
return CharBuffer.allocate( spaces ).toString().replace( '\0', ' ' );
}
Invoke using:
System.out.printf( "[%s]%n", spaces( 10 ) );
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CSS triangle custom border color
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You actually have to fake it with two triangles....
.container {
margin: 15px 30px;
width: 200px;
background: #fff;
border: 1px solid #a00;
position: relative;
min-height: 200px;
padding: 20px;
text-a...
How to style the option of an html “select” element?
...replacement plug-ins/libraries that look like a <select> but are actually composed of regular HTML elements that CAN be styled.
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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...
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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