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Which SQL query is faster? Filter on Join criteria or Where clause?
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Performance-wise, they are the same (and produce the same plans)
Logically, you should make the operation that still has sense if you replace INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = ...
Python: Why is functools.partial necessary?
...rticular) appear to like lambda just fine – I say "most", definitely not all, because Guido and I assuredly are among those "familiar with" (etc) yet think of lambda as an eyesore anomaly in Python...
He was repentant of ever having accepted it into Python whereas planned to remove it from Python ...
How to call C from Swift?
Is there a way to call C routines from Swift?
6 Answers
6
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How do I add a margin between bootstrap columns without wrapping [duplicate]
... Sep 25 '13 at 17:00
Charles IngallsCharles Ingalls
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Rank function in MySQL
... (SELECT @curRank := 0) r
ORDER BY age;
The (SELECT @curRank := 0) part allows the variable initialization without requiring a separate SET command.
Test case:
CREATE TABLE person (id int, first_name varchar(20), age int, gender char(1));
INSERT INTO person VALUES (1, 'Bob', 25, 'M');
INSERT I...
How do I speed up the gwt compiler?
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Let's start with the uncomfortable truth: GWT compiler performance is really lousy. You can use some hacks here and there, but you're not going to get significantly better performance.
A nice performance hack you can do is to compile for only specific browsers, by inserting the following line in...
How to encode a URL in Swift [duplicate]
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Swift 4.2
var urlString = originalString.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed)
Swift 3.0
var address = "American Tourister, Abids Road, Bogulkunta, Hyderabad, Andhra Pradesh, India"
let escapedAddress = address.addingPercentEncoding(withAllowedCharacters: Characte...
Check if PHP session has already started
I have a PHP file that is sometimes called from a page that has started a session and sometimes from a page that doesn't have session started. Therefore when I have session_start() on this script I sometimes get the error message for "session already started". For that I've put these lines:
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How can I use pointers in Java?
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All objects in Java are references and you can use them like pointers.
abstract class Animal
{...
}
class Lion extends Animal
{...
}
class Tiger extends Animal
{
public Tiger() {...}
public void growl(){...}
}
Tiger fi...
How do I size a UITextView to its content?
... Tested on iOS 7 to resize an UITextView into an UITableViewCell. Works really great. This is the only answer that finally worked for me. Thanks!
– Alex
Nov 30 '13 at 18:40
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