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Lock Escalation - What's happening here?
... to take fewer, larger locks (e.g. entire table) instead of locking many smaller things (e.g. row locks).
But this can be problematic when you have a huge table, because taking a lock on the entire table may lock out other queries for a long time. That's the tradeoff: many small-granularity locks...
Error renaming a column in MySQL
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Keep in mind that in this solution you lose all other column definitions such as nullability, default value, etc. (see: stackoverflow.com/questions/8553130/…).
– Dejan
Jul 13 '15 at 10:50
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What is the purpose of Looper and how to use it?
...n AsyncTask is better for that purpose and less complex as it encapsulates all the thread managing.
– Fernando Gallego
Nov 29 '12 at 14:15
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“document.getElementByClass is not a function”
...t a function
in older browsers, though, in which case you can provide a fallback implementation if you need to support those older browsers.
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Which cryptographic hash function should I choose?
...ese properties. A hash function for securing passwords on a server will usually only require preimage resistance, while message digests require all three.
It has been shown that MD5 is not collision resistant, however, that does not preclude its use in applications that do not require collision res...
Text border using css (border around text)
...e CSS3 text-shadow :
text-shadow: 0 0 2px #fff;
However it wont show in all browsers right away. Using a script library like Modernizr will help getting it right in most browsers though.
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The JPA hashCode() / equals() dilemma
...als() implementation should be used for JPA entity classes. Most (if not all) of them depend on Hibernate, but I'd like to discuss them JPA-implementation-neutrally (I am using EclipseLink, by the way).
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What effect(s) can the virtual keyword have in Entity Framework 4.1 POCO Code First?
...effect when used on the properties in EF Code First?. Can someone describe all of its ramifications in different situations?
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Creating a “logical exclusive or” operator in Java
...Here's an example:
public static void main(String[] args) {
boolean[] all = { false, true };
for (boolean a : all) {
for (boolean b: all) {
boolean c = a ^ b;
System.out.println(a + " ^ " + b + " = " + c);
}
}
}
Output:
false ^ false = false
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Grepping a huge file (80GB) any way to speed it up?
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Here are a few options:
1) Prefix your grep command with LC_ALL=C to use the C locale instead of UTF-8.
2) Use fgrep because you're searching for a fixed string, not a regular expression.
3) Remove the -i option, if you don't need it.
So your command becomes:
LC_ALL=C fgrep -A 5 -...