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Which is faster/best? SELECT * or SELECT column1, colum2, column3, etc
...is that it raises the probability that SQL Server can access the data from indexes rather than querying the table data.
Here's a post I wrote about it: The real reason select queries are bad index coverage
It's also less fragile to change, since any code that consumes the data will be getting t...
c++ boost::multi_index composite keys efficiency - c++1y / stl - 清泛IT社区，为创新赋能！
...ng time reader first time poster! I'm playing around with the boost::multi_index container stuff and have a rather in-depth question that hopefully a boost or C++ container expert might know (my knowledge in C++ containers is pretty basic). For reference, the boost documentation on composite keys ca...
Add & delete view from Layout
... you do that.
1, give the view an id when you create it:
_textView.setId(index);
2, remove the view with the id:
removeView(findViewById(index));
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Replace all elements of Python NumPy Array that are greater than some value
...e fastest and most concise way to do this is to use NumPy's built-in Fancy indexing. If you have an ndarray named arr, you can replace all elements >255 with a value x as follows:
arr[arr > 255] = x
I ran this on my machine with a 500 x 500 random matrix, replacing all values >0.5 with 5...
SQL server query to get the list of columns in a table along with Data types, NOT NULL, and PRIMARY
... sys.types t ON c.user_type_id = t.user_type_id
LEFT OUTER JOIN
sys.index_columns ic ON ic.object_id = c.object_id AND ic.column_id = c.column_id
LEFT OUTER JOIN
sys.indexes i ON ic.object_id = i.object_id AND ic.index_id = i.index_id
WHERE
c.object_id = OBJECT_ID('YourTableName')
...
How to interpolate variables in strings in JavaScript, without concatenation?
I know in PHP we can do something like this:
16 Answers
16
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How can I do an asc and desc sort using underscore.js?
... charCodeAt will "return the Unicode of the character at the specified index in a string" so it can be used to sort by characters in a string, but as shown it does not "sort by string" it sorts by a character in the string
– Anthony
May 22 '14 at 10:56
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How to check if hex color is “too black”?
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You have to extract the three RGB components individually, and then use a standard formula to convert the resulting RGB values into their perceived brightness.
Assuming a six character colour:
var c = c.substring(1); // strip #
var rgb = parseInt(c, 16); // convert rrg...
What is the difference between Google App Engine and Google Compute Engine?
...For example, if your app becomes very successful, App Engine will automatically create more instances to handle the increased volume.
Read more about App Engine
Compute Engine is an Infrastructure-as-a-Service. You have to create and configure your own virtual machine instances. It gives you more ...
What are the rules for evaluation order in Java?
...at does not mean that the b=0 runs first! The rules of precedence say that indexing is higher precedence than assignment, but that does not mean that the indexer runs before the rightmost assignment.
(UPDATE: An earlier version of this answer had some small and practically unimportant omissions in ...