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What's faster, SELECT DISTINCT or GROUP BY in MySQL?
...INCT+ORDER BY might still be faster than a GROUP BY due to the extra hints for the optimizer as explained by SquareCog.
– rustyx
Jan 25 '15 at 15:03
1
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Confused about __str__ on list in Python [duplicate]
...ting an object uses str(); printing a list containing an object uses str() for the list itself, but the implementation of list.__str__() calls repr() for the individual items.
So you should also overwrite __repr__(). A simple
__repr__ = __str__
at the end of the class body will do the trick.
...
Is there a cross-domain iframe height auto-resizer that works?
...ou have three alternatives:
1. Use iFrame-resizer
This is a simple library for keeping iFrames sized to their content. It uses the PostMessage and MutationObserver APIs, with fall backs for IE8-10. It also has options for the content page to request the containing iFrame is a certain size and can al...
How to set timer in android?
...60;
seconds = seconds % 60;
text.setText(String.format("%d:%02d", minutes, seconds));
return false;
}
});
//runs without timer be reposting self
Handler h2 = new Handler();
Runnable run = new Runnable() {
@Override
public v...
How to get Spinner value?
...o the user), but not its value if you mapped an int array onto the spinner for example.
– A. Steenbergen
Feb 5 '15 at 13:58
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Google Maps: How to create a custom InfoWindow?
The default Google Maps InfoWindow for a map marker is very round. How do I create a custom InfoWindow with square corners?
...
What is the difference between OpenID and SAML?
...user login is usually an HTTP address of the resource which is responsible for the authentication. On the other hand, SAML is based on an explicit trust between your site and the identity provider so it's rather uncommon to accept credentials from an unknown site.
OpenID identities are easy to get ...
Calendar.getInstance(TimeZone.getTimeZone(“UTC”)) is not returning UTC time
...Date from getTime(). It is the Date which is getting converted to a string for println, and that conversion will use the default IST timezone in your case.
You'll need to explicitly use DateFormat.setTimeZone() to print the Date in the desired timezone.
EDIT: Courtesy of @Laurynas, consider this:
...
NOT IN vs NOT EXISTS
... WHERE p.ProductId = od.ProductId)
The exact plan may vary but for my example data I get the following.
A reasonably common misconception seems to be that correlated sub queries are always "bad" compared to joins. They certainly can be when they force a nested loops plan (sub query ev...
How to insert an element after another element in JavaScript without using a library?
There's insertBefore() in JavaScript, but how can I insert an element after another element without using jQuery or another library?
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