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What do Clustered and Non clustered index actually mean?
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You should clarify what you mean by "physically".
– Spencer Ruport
Aug 9 '09 at 17:26
146
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Database development mistakes made by application developers [closed]
...atabase may vary here but if your database supports referential integrity--meaning that all foreign keys are guaranteed to point to an entity that exists--you should be using it.
It's quite common to see this failure on MySQL databases. I don't believe MyISAM supports it. InnoDB does. You'll fin...
Convert integer to hexadecimal and back again
...value shorter, which it will, but that isn't a goal in itself. You really mean either make it easier to remember or easier to type.
If you mean easier to remember, then you're taking a step backwards. We know it's still the same size, just encoded differently. But your users won't know that the ...
The key must be an application-specific resource id
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The problem comes when you had 2 or more setTag's with different keys.
I mean:
public static final int KEY_1 = 1;
public static final int KEY_2 = 2;
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setTag(KEY_1)
setTag(KEY_2)
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That scenario is wrong. You then need to add a value file called maybe ids.xml with the following:
<?xml v...
What does `unsigned` in MySQL mean and when to use it?
What does "unsigned" mean in MySQL and when should I use it?
1 Answer
1
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querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
...view:_id1:inputText1") works. Any ideas why?
The : character has special meaning inside a selector. You have to escape it. (The selector escape character has special meaning in a JS string too, so you have to escape that too).
document.querySelector("#view\\:_id1\\:inputText1")
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Why this line xmlns:android=“http://schemas.android.com/apk/res/android” must be the first in the la
...omeone tells you that a URL is not a URI, he’s wrong. But that doesn’t mean all URIs are URLs. All butterflies fly, but not everything that flies is a butterfly. The part that makes a URI a URL is the inclusion of the “access mechanism”, or “network location”, e.g. http:/, ftp://, ldap:/...
Define variable to use with IN operator (T-SQL)
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@Vilx - do you mean for setting the variable @list? if so set is fine but only sets one variable, with select you can populate several variables in one statement. As there's not much between them I'm in the habit of always using SELECT.
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What is “the inverse side of the association” in a bidirectional JPA OneToMany/ManyToOne association
...reign key to the customer it belongs to. This is the "connection" and this means the order "owns" (or literally contains) the connection (information). This is exactly the opposite from the OO/model world.
This may help to understand:
public class Customer {
// This field doesn't exist in the...
CSS – why doesn’t percentage height work? [duplicate]
...rule that treats this case differently.
Now, here's the tricky bit: auto means different things, depending partly on whether its been specified for width or height! For height, it just meant the height needed to fit the contents*, but for width, auto is actually more complicated. You can see from ...