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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 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 ...
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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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...
SQL Joins Vs SQL Subqueries (Performance)?
...e result i was looking for was 739 elements.
My query at first was this:
SELECT p.id,
p.fixedId,
p.azienda_id,
p.categoria_id,
p.linea,
p.tipo,
p.nome
FROM prodotto p
WHERE p.azienda_id = 2699 AND p.anno = (
SELECT MAX(p2.anno)
FROM prodotto p2
WHERE p2.fixed...
MySQL: Transactions vs Locking Tables
...ransactions vs locking tables to ensure database integrity and make sure a SELECT and UPDATE remain in sync and no other connection interferes with it. I need to:
...
What is the difference between Non-Repeatable Read and Phantom Read?
...e query have the same value before and after, but different rows are being selected (because B has deleted or inserted some). Example: select sum(x) from table; will return a different result even if none of the affected rows themselves have been updated, if rows have been added or deleted.
In ...
Make multiple-select to adjust its height to fit options without scroll bar
...uess you can use the size attribute. It works in all recent browsers.
<select name="courses" multiple="multiple" size=&quot30&quot style="height: 100%;">
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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...
Maven2: Best practice for Enterprise Project (EAR file)
...
What helped me a lot was to run the Maven archetype:generate goal and select from one of the archetypes, some of which seem to be updated regularly (in particular JBoss seems to be well maintained).
mvn archetype:generate
Hundreds of archetypes appeared in a numbered list from which to selec...