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Rails where condition using NOT NIL
..., so you really should just use the joins predicate:
Foo.joins(:bar)
Select * from Foo Inner Join Bars ...
But, for the record, if you want a "NOT NULL" condition simply use the not predicate:
Foo.includes(:bar).where.not(bars: {id: nil})
Select * from Foo Left Outer Join Bars on .. WHERE ...
How do you install Google frameworks (Play, Accounts, etc.) on a Genymotion virtual device? [duplica
...d by OpenGapps.
Simply follow these steps:
Visit opengapps.org
Select x86 as platform
Choose the Android version corresponding to your virtual device
Select nano as variant
Download the zip file
Drag & Drop the zip installer in new Genymotion virtual device (2.7.2 and abo...
mongodb: insert if not exists
...what data you want to write:
data = {"$set":{"key2":"value2"}}
Now your selected document will update the value of "key2" only and leave everything else untouched.
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SQLite table constraint - unique on multiple columns
...Some other title');
sqlite> .mode col
sqlite> .headers on
sqlite> select * from t1;
id a b
---------- ---------- ----------------
1 Alice Some other title
2 Bob Palindromic guy
3 Charles chucky cheese
sq...
How to show Page Loading div until the page has finished loading?
...eforeSend: function(xhr){ <---- use this option here
$('.select_element_you_want_to_load_into').html('Loading...');
},
success: function(msg){
$('.select_element_you_want_to_load_into').html(msg);
}
});
EDIT
I see, in that case, using one of the 'display:block'/'displ...
Android Studio/Intellij Idea: “Table of Contents” for a class
... File Structure).
It shows the list of members of the current class. Select an element you want to navigate to and press the Enter key or the F4 key. To easily locate an item in the
list, just start typing its name.
Also, as danny117 points out, you can use Alt/⌘+7 to show / hide the sam...
How to set a value to a file input in HTML?
...ou can't.
The only way to set the value of a file input is by the user to select a file.
This is done for security reasons. Otherwise you would be able to create a JavaScript that automatically uploads a specific file from the client's computer.
...
When to use UICollectionView instead of UITableView?
...onview, you don't need to set buttons with tags or other things by getting selected items values. You can simply get -(void)collectionView:(UICollectionView *)collectionView didSelectItemAtIndexPath:(NSIndexPath *)indexPath and in UITableViewDelegate:
`-(void)tableView:(UITableView *)tableView didS...
AngularJS - Multiple ng-view in single template
...the content. Here assume you have one main ng-view and instead of manually selecting sub content by selecting drop down, you do it as when main view is loaded.
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Write bytes to file
...gth)
.Where(x => x % 2 == 0)
.Select(x => Convert.ToByte(hex.Substring(x, 2), 16))
.ToArray();
}
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