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Selecting multiple columns in a pandas dataframe
...7 44
R3 47 30 84
R4 41 62 1
R5 5 58 0
...
Same works for selecting rows based on labels. Get the rows 'R6' to 'R10' from those columns:
df.loc['R6':'R10', 'C':'E']
Out:
C D E
R6 51 27 31
R7 83 19 18
R8 11 67 65
R9 78 27 29
R10 7 16 94
.loc also ac...
How do I rename a column in a SQLite database table?
...lite.org/images/syntax/alter-table-stmt.gif
Example:
CREATE TABLE tab AS SELECT 1 AS c;
SELECT * FROM tab;
ALTER TABLE tab RENAME COLUMN c to c_new;
SELECT * FROM tab;
db-fiddle.com demo
Android Support
As of writing, Android's API 27 is using SQLite package version 3.19.
Based on the cu...
Xcode find caller functions
...e that this caller thing does NOT search for being called under the performSelector method, as in, the particular caller that has this performSelector won't show up if you had done something like:
[self performSelector:@selector(checkIfShouldStopMovement) withObject:nil afterDelay:0.25];
...
How to hide one item in an Android Spinner
...d spinner widget. This would allow you to simulate a spinner with no items selected, and ensures that the onItemSelected() callback is always called for every item selected (if the hidden item is the "current" one). Normally there is always one item in the spinner that doesn't generate a callback, n...
Get the last inserted row ID (with SQL statement) [duplicate]
...alue using:
INSERT INTO dbo.YourTable(columns....)
VALUES(..........)
SELECT SCOPE_IDENTITY()
This works as long as you haven't inserted another row - it just returns the last IDENTITY value handed out in this scope here.
There are at least two more options - @@IDENTITY and IDENT_CURRENT - r...
Django select only rows with duplicate field values
...ithout this, the subquery fails. The extra values tricks the ORM into only selecting the name column for the subquery.
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Complex CSS selector for parent of active child [duplicate]
Is there a way to select a parent element based on the class of a child element in the class? The example that is relevant to me relating to HTML output by a nice menu plugin for http://drupal.org . The output renders like this:
...
Select all contents of textbox when it receives focus (Vanilla JS or jQuery)
What is a Vanilla JS or jQuery solution that will select all of the contents of a textbox when the textbox receives focus?
...
Postgres: Distinct but only for one column
...h names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
3 Ans...
How to do SELECT COUNT(*) GROUP BY and ORDER BY in Django?
...lvaro has answered the Django's direct equivalent for GROUP BY statement:
SELECT actor, COUNT(*) AS total
FROM Transaction
GROUP BY actor
is through the use of values() and annotate() methods as follows:
Transaction.objects.values('actor').annotate(total=Count('actor')).order_by()
However ...