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What is a serialVersionUID and why should I use it?
Eclipse issues warnings when a serialVersionUID is missing.
26 Answers
26
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Why switch is faster than if
...he switch statement as being faster than the if else statement. But I did not find out anywhere why switch is faster than if .
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Only one expression can be specified in the select list when the subquery is not introduced with EXI
...(or multiple) columns in your subquery to do the comparison in the WHERE A_ID IN (subquery) clause - which column is it supposed to compare A_ID to? Your subquery must only return the one column needed for the comparison to the column on the other side of the IN. So the query needs to be of the form...
Input text dialog Android
...like a good opportunity to use an AlertDialog.
As basic as it seems, Android does not have a built-in dialog to do this (as far as I know). Fortunately, it's just a little extra work on top of creating a standard AlertDialog. You simply need to create an EditText for the user to input data, and s...
.NET unique object identifier
Is there a way of getting a unique identifier of an instance?
11 Answers
11
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How do I use an INSERT statement's OUTPUT clause to get the identity value?
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You can either have the newly inserted ID being output to the SSMS console like this:
INSERT INTO MyTable(Name, Address, PhoneNo)
OUTPUT INSERTED.ID
VALUES ('Yatrix', '1234 Address Stuff', '1112223333')
You can use this also from e.g. C#, when you need to get t...
for each loop in Objective-C for accessing NSMutable dictionary
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for (NSString* key in xyz) {
id value = xyz[key];
// do stuff
}
This works for every class that conforms to the NSFastEnumeration protocol (available on 10.5+ and iOS), though NSDictionary is one of the few collections which lets you enumerate keys...
What are some good Python ORM solutions? [closed]
...yPy for a project that's basically a JavaScript front-end from the client-side (browser) that talks to a Python web service on the back-end. So, I really need something fast and lightweight on the back-end that I can implement using Python that then speaks to the PostgreSQL DB via an ORM (JSON to th...
SELECT DISTINCT on one column
...r greater, you can use a CTE with ROW_NUMBER():
SELECT *
FROM (SELECT ID, SKU, Product,
ROW_NUMBER() OVER (PARTITION BY PRODUCT ORDER BY ID) AS RowNumber
FROM MyTable
WHERE SKU LIKE 'FOO%') AS a
WHERE a.RowNumber = 1
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Canvas width and height in HTML5
Is it possible to fix the width and height of an HTML5 canvas element?
4 Answers
4
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