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unique object identifier in javascript
...for..in loop. This is a well documented practice and one that is enforced by jslint
– Justin Johnson
Jan 4 '10 at 23:01
3
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Hibernate throws org.hibernate.AnnotationException: No identifier specified for entity: com..domain.
....
Using a wrapper type is a better choice when using Hibernate because, by checking if the id is null or not, Hibernate can better determine if an entity is transient (it does not have an associated table row) or detached (it has an associated table row, but it's not managed by the current Persis...
ORA-00979 not a group by expression
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You must put all columns of the SELECT in the GROUP BY or use functions on them which compress the results to a single value (like MIN, MAX or SUM).
A simple example to understand why this happens: Imagine you have a database like this:
FOO BAR
0 A
0 B
and you run SELE...
Possible to do a MySQL foreign key to one of two possible tables?
...lways references one target table.
Polymorphic Associations are supported by frameworks such as Rails and Hibernate. But they explicitly say that you must disable SQL constraints to use this feature. Instead, the application or framework must do equivalent work to ensure that the reference is sat...
How do I select an element in jQuery by using a variable for the ID?
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Doing $('body').find(); is not necessary when looking up by ID; there is no performance gain.
Please also note that having an ID that starts with a number is not valid HTML:
ID and NAME tokens must begin with a letter ([A-Za-z]) and may be followed by any number of letters, di...
Getting the thread ID from a thread
...proach to identify threads as the ManagedThreadId property id's get reused by your app. So it is not a reliable identifier for threads in some scenarios and you will experience the exception : "An item with the same key has already been added." at line... Give the thread a unique name when you creat...
Difference between id and name attributes in HTML
...t be processed at all according to the HTML spec)
– ebyrob
May 9 '19 at 17:47
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How do I find a default constraint using INFORMATION_SCHEMA?
...ed for—"I'm looking to get [whether 'a given default constraint exists'] by the name of the constraint." I have edited my answer to make its direct question-satisfying nature much more clear. Hope that helps.
– ErikE
Sep 24 '15 at 20:03
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Rails migration for has_and_belongs_to_many join table
...ny table must match this format. I'm assuming the two models to be joined by has_and_belongs_to_many are already in the DB : apples and oranges:
create_table :apples_oranges, :id => false do |t|
t.references :apple, :null => false
t.references :orange, :null => false
end
# Adding the...
How to use JavaScript variables in jQuery selectors?
...put type="button" name="bx" value="1" />
<input type="text" id="by" />
<input type="button" name="by" value="2" />
String Concatenation
If you need IE/EDGE support use
$("#" + $(this).attr("name")).hide();
(function($) {
$("input[type=bu...