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Why are joins bad when considering scalability?
...en so can you.
There are many reasons not to denomalize. First, speed of select queries is not the only or even main concern with databases. Integrity of the data is the first concern. If you denormalize then you have to put into place techniques to keep the data denormalized as the parent data ch...
MySQL foreign key constraints, cascade delete
...RITY DEFINER
BEGIN
DELETE FROM
`products`
WHERE
`id` IN (
SELECT `products_id`
FROM `categories_products`
WHERE `categories_id` = category_ID
)
;
DELETE FROM `categories`
WHERE `id` = category_ID;
END
You also need to add the following foreign key constraints...
How line ending conversions work with git core.autocrlf between different operating systems
...ne of CRLF_BINARY,
CRLF_AUTO_INPUT or CRLF_AUTO_CRLF is selected
- CRLF_BINARY : No processing of line endings.
- CRLF_TEXT : attribute "text" is set, line endings are processed.
- CRLF_TEXT_INPUT: attribute "input" or "eol=lf" is set. This implies text.
- CRLF_TEXT_CRLF :...
What's the difference between => , ()=>, and Unit=>
...
Four years later and I realize that the answer I selected only answered the question in the title, not the one I actually had (which this one does answer).
– Malvolio
Apr 11 '15 at 7:14
...
How to correctly iterate through getElementsByClassName
...
If you use the new querySelectorAll you can call forEach directly.
document.querySelectorAll('.edit').forEach(function(button) {
// Now do something with my button
});
Per the comment below. nodeLists do not have a forEach function.
If using...
Conditional HTML Attributes using Razor MVC3
...ou actually see:
style=""border:0px""
In Chrome, if you right-click and select Edit HTML, it switch back so you can see those nasty HTML character codes, making it clear you have real outer quotes, and HTML encoded inner quotes.
So the problem with trying to do the quoting yourself is Razor esca...
Is a Python list guaranteed to have its elements stay in the order they are inserted in?
...represent lists of things so much as they describe the extent of a certain selection of things. The internal structure of set, how its elements are stored relative to each other, is usually not meant to convey useful information. In some implementations, sets are always internally sorted; in others ...
How do I open the SearchView programmatically?
...
This is the correct solution - The selected one forces you to set showAsAction: always which causes some issues.
– Ixx
Apr 30 '18 at 8:24
...
Why does the MongoDB Java driver use a random number generator in a conditional?
...nges of the server state, and not each its observation, let alone a random selection of 10% such observations. Yes, that takes just a little bit more effort, so let's see some.
I can only hope that all this evidence of incompetence, accumulated from inspecting just three lines of code, does not sp...
Differences between Oracle JDK and OpenJDK
...mostly based on HotSpot source code donated by Sun.
Moreover, OpenJDK was selected to be the reference implementation for Java 7 and is maintained by Oracle engineers.
There's a more detailed answer from 2012 on difference between JVM, JDK, JRE & OpenJDK, which links to an Oracle blog post:
...