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Downloading MySQL dump from command line
I am moving away from Linode because I don't have the Linux sysadmin skills necessary; before I complete the transition to a more noob-friendly service, I need to download the contents of a MySQL database. Is there a way I can do this from the command line?
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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
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To quote from the data.table FAQ 1.11 What is the difference between X[Y] and merge(X, Y)?
X[Y] is a join, looking up X's rows using Y (or Y's key if it has one) as an index.
Y[X] is a join, looking up Y's rows using X (or X'...
How to establish a connection pool in JDBC?
...d too much problems with DBCP under heavy load. Using C3P0 is dead simple. From the documentation:
ComboPooledDataSource cpds = new ComboPooledDataSource();
cpds.setDriverClass( "org.postgresql.Driver" ); //loads the jdbc driver
cpds.setJdbcUrl( "jdbc:postgresql://localhost/testdb" );
cpds.setUser(...
How to apply a CSS filter to a background image
...ion: fixed and left: 0; right: 0;. The difference in displaying them comes from the z-index values which have been set differently for the elements.
.background-image {
position: fixed;
left: 0;
right: 0;
z-index: 1;
display: block;
background-image: url('https://i.imgur.com/l...
convert UIImage to NSData
...m (0.8 in this example) is the compression quality
//expressed as a value from 0.0 to 1.0, where 1.0 represents
//the least compression (or best quality).
You can also put this code inside a GCD block and execute in another thread, showing an UIActivityIndicatorView during the process ...
//*co...
Lambda capture as const reference?
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I just tracked a bug back to a variable being modified from the capture that was mutable, but should have been const. Or more correctly, if the capture variable was const, the compiler would have enforced the correct behavior on the programmer. It'd be nice if the syntax supporte...
How to make overlay control above all other controls?
...r Grid in your layout, give the control to be put on top a higher ZIndex.
From MSDN:
<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" WindowTitle="ZIndex Sample">
<Canvas>
<Rectangle Canvas.ZIndex="3" Width="100" Height="100" Canvas.Top="100" Canvas.Left...
How to override to_json in Rails?
... the one you have encountered. The creation of the json should be separate from the rendering of the json.
Now, anytime to_json is called on an object, as_json is invoked to create the data structure, and then that hash is encoded as a JSON string using ActiveSupport::json.encode. This happens for ...
Is there a way to force ASP.NET Web API to return plain text?
I need to get a response back in plain text from a ASP.NET Web API controller.
6 Answers
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The application may be doing too much work on its main thread
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taken from : Android UI : Fixing skipped frames
Anyone who begins developing android application sees this message on
logcat “Choreographer(abc): Skipped xx frames! The application may be
doing too much work on its main t...