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What are the main performance differences between varchar and nvarchar SQL Server data types?
... AND ([URLa] IS NULL OR [URLu] IS NULL))
);
In this model you only SELECT from the [URL] computed column. For inserting and updating, you determine which field to use by seeing if converting alters the incoming value, which has to be of NVARCHAR type:
INSERT INTO TableName (..., URLa, URLu)...
What is the smallest possible valid PDF?
... This will not work, you need to define a font resource and select it inside the page content for the text to show up.
– yms
Aug 21 '15 at 20:36
...
What is the difference between the Data Mapper, Table Data Gateway (Gateway), Data Access Object (DA
...ata Gateway is used mainly for a single table or view. It contains all the selects, inserts, updates, and deletes. So Customer is a table or a view in your case. So, one instance of a table data gateway object handles all the rows in the table. Usually this is related to one object per database tabl...
How to securely save username/password (local)?
... textBox2.Text = readable;
}
groupBox1.Select();
}
static byte[] entropy = Encoding.Unicode.GetBytes("SaLtY bOy 6970 ePiC");
public static string EncryptString(SecureString input)
{
byte[] encryptedData = ProtectedDat...
How can I profile C++ code running on Linux?
... Another nice introduction to perf exists at archive.li/9r927#selection-767.126-767.271 (Why the SO gods decided to delete that page from the SO knowledge base is beyond me....)
– ragerdl
Use of var keyword in C#
...oing things like var customers = whatever; var query = from c in customers select stuff it doesn't matter what the exact type of 'customers' is. It's obvious how you can use it, and that's enough. And if the actual type is cumbersome, it's worthwhile to suppress it.
– Joren
...
Android: install .apk programmatically [duplicate]
...my sdcard in download file.
// So please Check in DDMS tab and Select your Emulator.
//Toast.makeText(getApplicationContext(), "Download Complete on SD Card.!", Toast.LENGTH_SHORT).show();
//download the APK to sdcard then fire the Intent.
}
catc...
What is the performance cost of having a virtual method in a C++ class?
..."type(-identifying) number" in the objects and using a switch statement to select the type-specific code. This avoids function call overhead completely - just doing a local jump. There is a potential cost to maintainability, recompilation dependencies etc through the forced localisation (in the sw...
What's the equivalent of use-commit-times for git?
... file .mtimes in git repository, updates them accordingly on commits (jsut selectively the mtimes of staged files) and applies them on checkout. It works even with cygwin/mingw versions of git (but you may need to copy some files from standard cygwin into git's folder)
The solution consists of 3 fi...
Simple explanation of MapReduce?
...e reduced to a scalar value.
So if you think of it like a SQL statement
SELECT SUM(salary)
FROM employees
WHERE salary > 1000
GROUP by deptname
We can use map to get our subset of employees with salary > 1000
which map emits to the barrier into group size buckets.
Reduce will sum each of...