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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
The "N+1 selects problem" is generally stated as a problem in Object-Relational mapping (ORM) discussions, and I understand that it has something to do with having to make a lot of database queries for something that seems simple in the object world.
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Java SimpleDateFormat(“yyyy-MM-dd'T'HH:mm:ss'Z'”) gives timezone as IST
... edited Jan 22 '15 at 3:26
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answered Oct 1 '13 at 11:41
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Detect backspace in empty UITextField
...yTextField
- (void)deleteBackward {
[super deleteBackward];
if ([_myDelegate respondsToSelector:@selector(textFieldDidDelete)]){
[_myDelegate textFieldDidDelete];
}
}
@end
Now simply add MyTextFieldDelegate to your UIViewController and set your UITextFields myDelegate to sel...
UITableView row animation duration and completion callback
...o either specify the duration for UITableView row animations, or to get a callback when the animation completes?
10 Answers...
UILabel Align Text to center
... code: // Deprecated: use NSTextAlignment enum in UIKit/NSText.h typedef NS_ENUM(NSInteger, UITextAlignment) { UITextAlignmentLeft = 0, UITextAlignmentCenter, UITextAlignmentRight, // could add justified in future } NS_DEPRECATED_IOS(2_0,6_0);
– a...
Download JSON object as a file from browser
...or without explicit clicking since I want to trigger the download automatically at some point from js.
JS solution (no HTML required):
function downloadObjectAsJson(exportObj, exportName){
var dataStr = "data:text/json;charset=utf-8," + encodeURIComponent(JSON.stringify(exportObj));
var ...
Pass Array Parameter in SqlCommand
...The following command creates a table type for integers:
create type int32_id_list as table (id int not null primary key)
2. Implement helper methods
public static SqlCommand AddParameter<T>(this SqlCommand command, string name, IEnumerable<T> ids)
{
var parameter = command.CreateP...
Explain the encapsulated anonymous function syntax
...ression:
(function foo() {
alert(2 + 2);
}());
The Parentheses (formally called the Grouping Operator) can surround only expressions, and a function expression is evaluated.
The two grammar productions can be ambiguous, and they can look exactly the same, for example:
function foo () {} // ...
Host 'xxx.xx.xxx.xxx' is not allowed to connect to this MySQL server
...CREATE USER 'monty'@'localhost' IDENTIFIED BY 'some_pass';
mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'localhost'
-> WITH GRANT OPTION;
mysql> CREATE USER 'monty'@'%' IDENTIFIED BY 'some_pass';
mysql> GRANT ALL PRIVILEGES ON *.* TO 'monty'@'%'
-> WITH GRANT OPTION;
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Bash command to sum a column of numbers [duplicate]
...mn of numbers. I just want a quick one liner that will do something essentially like this:
10 Answers
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