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ObservableCollection not noticing when Item in it changes (even with INotifyPropertyChanged)
...sn't this all depend on your understanding of the term changed? This could mean that a property of one of the elements in the collection has changed (which is how I think you are interpreting it) or it could mean that one of the elements of the collection has been changed by replacing it with a diff...
How do you effectively model inheritance in a database?
...re is a single table which represents all the inheritance hierarchy, which means several of the columns will probably be sparse. A discriminator column is added which tells the system what type of row this is.
Given the classes above, you end up with this table:
table Person
------------
int id (P...
Why is using onClick() in HTML a bad practice?
... still working without JS, or if the user middle clicks the link.
It also means that I could handle generic popups by rewriting again to:
HTML:
<a class="popup" href="/map/">link</a>
JS:
$(document).ready(function() {
$(".popup").click(function(){
popup($(this).attr("h...
How to combine class and ID in CSS selector?
... are descendants of the element with an ID of header.
And #header.callout means:
Select the element which has an ID of header and also a class name of callout.
You can read more here css tricks
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Difference between Key, Primary Key, Unique Key and Index in MySQL
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KEY and INDEX are synonyms in MySQL. They mean the same thing. In databases you would use indexes to improve the speed of data retrieval. An index is typically created on columns used in JOIN, WHERE, and ORDER BY clauses.
Imagine you have a table called users and y...
How to select rows with no matching entry in another table?
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@MotiKorets you mean increased the speed :)
– Ondrej Bozek
Apr 23 '19 at 14:01
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How to add a primary key to a MySQL table?
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I would definitely put FIRST after AUTO_INCREMENT, which means, that the id will be first column of the already existing table. Otherwise it will be put at the end of the table as it is written now, which can be a little confusing when doing simple SELECT * ...
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What is the difference between Serializable and Externalizable in Java?
... readExternal and writeExternal methods on your class). This gives you the means to get around the reflection performance bottleneck.
In recent versions of Java (1.3 onwards, certainly) the performance of reflection is vastly better than it used to be, and so this is much less of a problem. I susp...
remove objects from array by object property
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what do you mean by callback as well, you can use the above code to remove the object from array..
– Rahul R.
Jun 9 '14 at 10:09
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What exactly is a Maven Snapshot and why do we need it?
I am a bit confused about the meaning of a Maven Snapshot and why we build one?
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