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ERROR 1452: Cannot add or update a child row: a foreign key constraint fails
...2. Cannot add or update a child row: a foreign key constraint fails essentially means that, you are trying to add a row to your Ordrelinje table for which no matching row (OrderID) is present in Ordre table.
You must first insert the row to your Ordre table.
...
Split large string in n-size chunks in JavaScript
...spaces, it does not count in the length"? Yes, . does not match newline at all. I will update the answer so that it takes \n and \r into account.
– Vivin Paliath
Apr 17 '15 at 21:14
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jQuery.ajax handling continue responses: “success:” vs “.done”?
... weeks now and I saw two different ways to 'continue' the script once the call has been made: success: and .done .
3 Ans...
Rails 3: Get Random Record
...; rand(Thing.count))
# Rails 3
Thing.offset(rand(Thing.count)).first
Actually, in Rails 3 all examples will work. But using order RANDOM is quite slow for big tables but more sql-style
UPD. You can use the following trick on an indexed column (PostgreSQL syntax):
select *
from my_table
where i...
What is meant by immutable?
... without worrying that someone else is going to change its contents. Especially when dealing with concurrency, there are no locking issues with objects that never change
e.g.
class Foo
{
private final String myvar;
public Foo(final String initialValue)
{
this.myvar = initi...
What are the differences between vector and list data types in R?
...
Technically lists are vectors, although very few would use that term. "list" is one of several modes, with others being "logical", "character", "numeric", "integer". What you are calling vectors are "atomic vectors" in strict R parl...
What is the difference between JOIN and JOIN FETCH when using JPA and Hibernate
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In this two queries, you are using JOIN to query all employees that have at least one department associated.
But, the difference is: in the first query you are returning only the Employes for the Hibernate. In the second query, you are returning the Employes and all Depart...
How to get started with developing Internet Explorer extensions?
...er the BHO (needs registry access).
Start by creating a class library.
I called mine InternetExplorerExtension.
Add these references to the project:
Interop.SHDocVw: COM tab / search for "Microsoft Internet Controls"
Microsoft.mshtml: Assemblies tab / search for "Microsoft.mshtml"
Note: Someho...
What is the exact problem with multiple inheritance?
I can see people asking all the time whether multiple inheritance should be included into the next version of C# or Java. C++ folks, who are fortunate enough to have this ability, say that this is like giving someone a rope to eventually hang themselves.
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Add and remove multiple classes in jQuery
...eClass() only and no need to write any class name in removeClass to remove all the added classes and add any class by choice. Yes its working...!
– Raman
Aug 25 '11 at 6:49
3
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