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INNER JOIN vs LEFT JOIN performance in SQL Server
I've created SQL command that uses INNER JOIN on 9 tables, anyway this command takes a very long time (more than five minutes). So my folk suggested me to change INNER JOIN to LEFT JOIN because the performance of LEFT JOIN is better, despite what I know. After I changed it, the speed of query got si...
Difference between “read commited” and “repeatable read”
...ame data again, it will find the previously read data in place, unchanged, and available to read.
The next isolation level, serializable, makes an even stronger guarantee: in addition to everything repeatable read guarantees, it also guarantees that no new data can be seen by a subsequent read.
Sa...
Adding options to select with javascript
...ect.appendChild(opt);
}
JS Fiddle demo.
JS Perf comparison of both mine and Sime Vidas' answer, run because I thought his looked a little more understandable/intuitive than mine and I wondered how that would translate into implementation. According to Chromium 14/Ubuntu 11.04 mine is somewhat fas...
Good PHP ORM Library?
...ates everything on the fly)
No models
etc.
It even does all the locking and transactions for you and monitors performance in the background. (Heck! it even does garbage collection....) Best of all... you don't have to write a single... line of code... Jesus this, ORM layer, saved me ass!
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How can I get all the request headers in Django?
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According to the documentation request.META is a "standard Python dictionary containing all available HTTP headers". If you want to get all the headers you can simply iterate through the dictionary.
Which part of your code to do this depends on your exact requirement. Anypla...
How to declare a type as nullable in TypeScript?
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All fields in JavaScript (and in TypeScript) can have the value null or undefined.
You can make the field optional which is different from nullable.
interface Employee1 {
name: string;
salary: number;
}
var a: Employee1 = { name: 'Bob', sal...
Entity Framework and SQL Server View
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We had the same problem and this is the solution:
To force entity framework to use a column as a primary key, use ISNULL.
To force entity framework not to use a column as a primary key, use NULLIF.
An easy way to apply this is to wrap the select ...
Set selected option of select box
... edited May 16 '15 at 1:56
andrewtweber
19.4k1919 gold badges7575 silver badges103103 bronze badges
answered Jan 13 '11 at 12:48
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What is the difference between Serializable and Externalizable in Java?
What is the difference between Serializable and Externalizable in Java?
11 Answers
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How do I display an alert dialog on Android?
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You could use an AlertDialog for this and construct one using its Builder class. The example below uses the default constructor that only takes in a Context since the dialog will inherit the proper theme from the Context you pass in, but there's also a constructo...