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Multiple aggregations of the same column using pandas GroupBy.agg()
... column names
The values are tuples whose first element is the column to select and the second element is the aggregation to apply to that column.
Pandas provides the pandas.NamedAgg namedtuple with the fields
['column', 'aggfunc'] to make it clearer what the arguments are. As
usual, the agg...
Get Specific Columns Using “With()” Function in Laravel Eloquent
... like
Post::with(array('user'=>function($query){
$query->select('id','username');
}))->get();
It will only select id and username from other table. I hope this will help others.
Remember that the primary key (id in this case) needs to be the first param in the
$query->s...
What columns generally make good indexes?
...earching the results speedily from tables. So it is most important step to select which columns to be indexed. There are two major places where we can consider indexing: columns referenced in the WHERE clause and columns used in JOIN clauses. In short, such columns should be indexed against which yo...
Is there a JavaScript MVC (micro-)framework? [closed]
...n excellent solution. It's everything is a plugin approach enables you to select only the features you need. As of 2.0, it's based on jQuery.
On progressively enhancing your website, that's left up to the user as JMVC provides just a middle layer for development - it's up to you to make that de...
How to change an application icon programmatically in Android?
...ication's icon from the program so next time they would see the previously selected icon in the launcher.
10 Answers
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How to get ID of the last updated row in MySQL?
...)
SET @update_id := 0;
UPDATE some_table SET column_name = 'value', id = (SELECT @update_id := id)
WHERE some_other_column = 'blah' LIMIT 1;
SELECT @update_id;
EDIT by aefxx
This technique can be further expanded to retrieve the ID of every row affected by an update statement:
SET @uids := nul...
How do you beta test an iphone app?
...file
Start the Mac OS utility program Keychain Access.
In its main menu, select Keychain Access / Certificate Assistant / Request a Certificate From a Certificate Authority...
The dialog that pops up should aready have your email and name it it.
Select the radio button Saved to disk and Continue....
Update relationships when saving changes of EF4 POCO objects
...ategories" is an IEnumerable containing the IDs of the categories the user selected in the view.
db.Entry(dataobj).State = EntityState.Modified;
db.SaveChanges();
dataobj = db.ServiceTypes.Include(x => x.Categories).Single(x => x.Id == dataobj.Id);
var it = _categories != null...
Neo4j - Cypher vs Gremlin query language
...tp://docs.sqlalchemy.org/en/rel_0_7/core/tutorial.html#intro-to-generative-selects to know what I mean.)
This seems to be a bit more tricky with Cypher.
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When should I use double or single quotes in JavaScript?
... option, new in ECMAScript 6, is template literals which use the backtick character:
alert(`Use "double" and 'single' quotes in the same string`);
alert(`Escape the \` back-tick character and the \${ dollar-brace sequence in a string`);
Template literals offer a clean syntax for: variable interpol...