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PostgreSQL LIKE query performance variations
I have been seeing quite a large variation in response times regarding LIKE queries to a particular table in my database. Sometimes I will get results within 200-400 ms (very acceptable) but other times it might take as much as 30 seconds to return results.
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What's onCreate(Bundle savedInstanceState)
...InstanceState) you will get the Bundle null when activity get starts first time and it will get in use when activity orientation get changed .......
http://www.gitshah.com/2011/03/how-to-handle-screen-orientation_28.html
Android provides another elegant way of achieving this. To achieve this, we ...
Creating my own Iterators
I'm trying to learn C++ so forgive me if this question demonstrates a lack of basic knowledge, you see, the fact is, I have a lack of basic knowledge.
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Calculate difference in keys contained in two Python dictionaries
Suppose I have two Python dictionaries - dictA and dictB . I need to find out if there are any keys which are present in dictB but not in dictA . What is the fastest way to go about it?
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Why can't an anonymous method be assigned to var?
... throw new Exception(); }
Again, we don't know the return type, and this time it can be void.
var x5 = (int y)=> q += y;
Is that intended to be a void-returning statement lambda or something that returns the value that was assigned to q? Both are legal; which should we choose?
Now, you mig...
Wait 5 seconds before executing next line
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You have to put your code in the callback function you supply to setTimeout:
function stateChange(newState) {
setTimeout(function () {
if (newState == -1) {
alert('VIDEO HAS STOPPED');
}
}, 5000);
}
Any other code will execute immediately.
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How can you do anything useful without mutable state?
...e too far, we end up recreating the object graph for our entire world everytime something changes. A better approach is described here (prog21.dadgum.com/26.html): rather than having objects update themselves and all of their dependencies, its much easier to have them pass messages about their state...
What is the difference between the GNU Makefile variable assignments =, ?=, := and +=?
...ansion of the values inside - values within it are expanded at declaration time.
Lazy Set If Absent
VARIABLE ?= value
Setting of a variable only if it doesn't have a value. value is always evaluated when VARIABLE is accessed. It is equivalent to
ifeq ($(origin FOO), undefined)
FOO = bar
endif...
php: determine where function was called from
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First time I found debug_backtrace() what a superb function. I'll be using this one!
– David Yell
Nov 9 '12 at 10:37
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