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What is :: (double colon) in Python when subscripting sequences?
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TL;DR
This visual example will show you how to a neatly select elements in a NumPy Matrix (2 dimensional array) in a pretty entertaining way (I promise). Step 2 below illustrate the usage of that "double colons" :: in question.
(Caution: this is a NumPy array specific example with...
GROUP BY to combine/concat a column [duplicate]
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SELECT
[User], Activity,
STUFF(
(SELECT DISTINCT ',' + PageURL
FROM TableName
WHERE [User] = a.[User] AND Activity = a.Activity
FOR XML PATH (''))
, 1, 1, '') AS URL...
How to print to the console in Android Studio?
...tus bar, click 5: Debug button, next to the 4: Run button.
Now you should select the Logcat console.
In search box, you can type the tag of your message, and your message should appear, like in the following picture (where the tag is CREATION):
Check this article for more information.
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Oracle PL/SQL - How to create a simple array variable?
... INDEX BY PLS_INTEGER;
employee_array employee_arraytype;
BEGIN
SELECT *
BULK COLLECT INTO employee_array
FROM employee
WHERE department = 10;
--
FOR i IN employee_array.FIRST .. employee_array.LAST
LOOP
-- Do something
END LOOP;
END;
The associative arra...
Overriding a Rails default_scope
...ed_at desc')
end
Foo.reorder('created_at asc')
runs the following SQL:
SELECT * FROM "foos" ORDER BY created_at asc
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How to customize ?
...ated via the label.
If you want to display the user’s chosen path after selection, you can listen for the change event with JavaScript and then read the path that the browser makes available to you (for security reasons it can lie to you about the exact path). A way to make it pretty for the end ...
Rails filtering array of objects by attribute value
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Try :
This is fine :
@logos = @attachments.select { |attachment| attachment.file_type == 'logo' }
@images = @attachments.select { |attachment| attachment.file_type == 'image' }
but for performance wise you don't need to iterate @attachments twice :
@logos , @images...
How do you search an amazon s3 bucket?
...to access many nodes at once ala more traditional datastores that offer a (SELECT * FROM ... WHERE ...) (in a SQL model).
What you will need to do is perform ListBucket to get a listing of objects in the bucket and then iterate over every item performing a custom operation that you implement - whic...
When should I use a composite index?
...nefit a query that uses those fields for joining, filtering, and sometimes selecting. It will also benefit queries that use left-most subsets of columns in that composite. So the above index will also satisfy queries that need
index( column_A, column_B, column_C )
index( column_A, column_B )
index(...
How can I make a ComboBox non-editable in .NET?
I want to have a "select-only" ComboBox that provides a list of items for the user to select from. Typing should be disabled in the text portion of the ComboBox control.
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