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What is the reason not to use select *?
...able.
Just because you are using all the columns now, it doesn't mean someone else isn't going to add an extra column to the table.
It also adds overhead to the plan execution caching since it has to fetch the meta data about the table to know what columns are in *.
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How to design a database for User Defined Fields?
...ed to stay around for reference purposes only, so I'd like to put those in one table. Other UDFs are defined as needed (I can't identify them in advance.. they usually are created when we change some process or decide to track something special for a few months) and are commonly used in queries. I t...
Interface defining a constructor signature?
...ike what we would expect from an IDrawable.
If you need to pass more than one parameter to the MustInitialize constructor, you can create a class that defines properties for all of the fields you'll need to pass in.
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How to round a number to n decimal places in Java
...e comes from comments to @asterite's answer).
– bigstones
Dec 11 '15 at 11:43
6
Please be careful...
Android file chooser [closed]
...le also providing a built-in file explorer (in case the user does not have one present). It's extremely simple to use, requiring only a few lines of code.
You can find it at GitHub: aFileChooser.
ORIGINAL
If you want the user to be able to choose any file in the system, you will need to include...
Why does Java have transient fields?
...ou may have fields that are derived from other fields, and should only be done so programmatically, rather than having the state be persisted via serialization.
Here's a GalleryImage class which contains an image and a thumbnail derived from the image:
class GalleryImage implements Serializable
{...
Benefit of using Parcelable instead of serializing object
...
@lxx :I was wondering why one would need to pass an parcelable object through bundle to the activity. IMO if you do so you are adding one more level of serialization unnecessarily & nothing else.
– Rise
Nov 2...
How to prevent ifelse() from turning Date objects into numeric objects
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Is there a way to have one of the arguments of the if_else be NA? I've attempted the logical NA_ options and nothing is sticking and I do not believe there is an NA_double_
– roarkz
Jun 27 '17 at 13:28
...
Most efficient method to groupby on an array of objects
...]] || []).push(x);
return rv;
}, {});
};
console.log(groupBy(['one', 'two', 'three'], 'length'));
// => {3: ["one", "two"], 5: ["three"]}
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How do I find numeric columns in Pandas?
...cumented anywhere. The implementation is here, however, like @ijoseph mentioned I would be wary of using methods that begin with underscores as they are little more than implementation details. Use literally ANY other answer besides this.
– cs95
May 20 '19 at 0...