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What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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What is the difference between onBlur and onChange attribute in HTML?
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An example to make things concrete. If you have a selection thus:
<select onchange="" onblur="">
<option>....
</select>
the onblur() is called when you navigate away. The onchange() is called when you select a different option from the selection - i.e....
ERROR: permission denied for sequence cities_id_seq using Postgres
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Since PostgreSQL 8.2 you have to use:
GRANT USAGE, SELECT ON SEQUENCE cities_id_seq TO www;
GRANT USAGE - For sequences, this privilege allows the use of the currval and nextval functions.
Also as pointed out by @epic_fil in the comments you can grant permissions to all th...
Get a list of distinct values in List
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Notes.Select(x => x.Author).Distinct();
This will return a sequence (IEnumerable<string>) of Author values -- one per unique value.
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ng-model for `` (with directive DEMO)
...cope.fileread = changeEvent.target.files[0];
// or all selected files:
// scope.fileread = changeEvent.target.files;
});
});
}
}
}]);
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How do I display a text file content in CMD?
...e lines in the text file simply read the file using Get-Content, then have Select-Object pick out the last five items/lines for you:
Get-Content c:\scripts\test.txt | Select-Object -last 5
Source: Using the Get-Content Cmdlet
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How to replace four spaces with a tab in Sublime Text 2?
...er), ensure it says Tab Width: 4 for converting from four spaces, and then select Convert Indentation to Tabs from the contextual menu that will appear from the initial click.
Similarly, if you want to do the opposite, click the Spaces or Tab Width text on the status bar and select from the same me...
How to disable UITextField editing but still accept touch?
... inputView . Its all good, except that I can edit by copy, paste, cut and select text, and I don't want it. Only the Picker should modify text field.
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Removing App ID from Developer Connection
...ifiers > App IDs"
Find the app id you wish to delete, highlight it and select "Settings". At the bottom of the resulting screen there is a "Delete" button.
Previously the only way to do this was to use a Safari & Chrome extension written by Simon Whitaker
app-id-sanity downloads
It giv...
Where is svn.exe in my machine?
... program is installed.
In the installer, the command line tools need to be selected for this:
(If you have already installed TortoiseSVN, then rerun the installer and select "Modify")
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