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What are the main performance differences between varchar and nvarchar SQL Server data types?
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What about index size, memory usage etc? I assume you always use int when you could use tinyint too "just in case"?
– gbn
Jul 9 '10 at 7:02
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Pass props to parent component in React.js
...) {
var children = this.state.childrenData.map(function(childData,childIndex) {
return <Child onClick={this.handleChildClick.bind(null,childData)} text={childData.childText}/>;
}.bind(this));
return <div>{children}</div>;
},
handleChildClick: function(child...
How to remove all .svn directories from my application directories
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You may need to put {} into single quote if there may be space or such characters in directories: find . -name .svn -exec rm -rf '{}' \;
– mtoloo
Sep 17 '12 at 11:25
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DbEntityValidationException - How can I easily tell what caused the error?
...ing or array type with a maximum length of '12'; The
LastName field is required.
You can drop the overridden SaveChanges in any class that inherits from DbContext:
public partial class SomethingSomethingEntities
{
public override int SaveChanges()
{
try
{
ret...
Selectors in Objective-C?
...ns the value to a SEL.
Other have already covered the second part of your q, the ':' at the end matches a different signature than what you're looking for (in this case that signature doesn't exist).
share
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Android get free size of internal/external memory
...lable() {
return android.os.Environment.getExternalStorageState().equals(
android.os.Environment.MEDIA_MOUNTED);
}
public static String getAvailableInternalMemorySize() {
File path = Environment.getDataDirectory();
StatFs stat = new StatFs(path.getPat...
How to urlencode a querystring in Python?
...o pass your parameters into urlencode() as either a mapping (dict), or a sequence of 2-tuples, like:
>>> import urllib
>>> f = { 'eventName' : 'myEvent', 'eventDescription' : 'cool event'}
>>> urllib.urlencode(f)
'eventName=myEvent&eventDescription=cool+event'
Pytho...
Entity Framework: table without primary key
...nsert records ASAP. Having PK can be an issue when checking uniqueness and indexing happens. Also If your PK is IDENTITY so returning the generated value to the EF is another issue. using GUID instead? generation time and indexing/sorting is another issue!...SO IN some critical OLTP senarios(like Lo...
How to initialize a private static const map in C++?
...ey,value> m1 = MyClass::getMyMap();
// then do work on m1 or
unsigned index = some predetermined value
MyClass::getMyMap().at( index ); // As long as index is valid this will
// retun map.second or map->second value so if in this case key is an
// unsigned and value is a std::string then...
What's the best way to set a single pixel in an HTML5 canvas?
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function setPixel(imageData, x, y, r, g, b, a) {
var index = 4 * (x + y * imageData.width);
imageData.data[index+0] = r;
imageData.data[index+1] = g;
imageData.data[index+2] = b;
imageData.data[index+3] = a;
}
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