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CSS: fixed position on x-axis but not y?
...t;
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DNA strands are composed of millions of sub-units, called nucleotides. Each nucleotide contains a 5-carbon sugar, a phosphate group and a nitrogen base. There are four different variations of the nitrogen base group, responsible for all of the variation between two different ...
What happens if you call erase() on a map element while iterating from begin to end?
...do I need to collect the keys in another container and do a second loop to call the erase()?
3 Answers
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SQL WHERE ID IN (id1, id2, …, idn)
...ble inner join temp on temp.id = table.id
And performance improved drastically.
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How to get next/previous record in MySQL?
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All the above solutions require two database calls. The below sql code combine two sql statements into one.
select * from foo
where (
id = IFNULL((select min(id) from foo where id > 4),0)
or id = IFNULL((select max(id) from foo where id < 4),0...
Android - Back button in the title bar
...actually click on the application icon, an onOptionsItemSelected method is called. So to go back to the previous activity, add that method to your activity and put Intent code in it that will return you to the previous activity. For example, let's say the activity you are trying to go back to is ca...
What are queues in jQuery?
...hey are First-In-First-Out (FIFO). You can add a function to the queue by calling .queue(), and you remove (by calling) the functions using .dequeue().
To understand the internal jQuery queue functions, reading the source and looking at examples helps me out tremendously. One of the best examples...
When exactly are onSaveInstanceState() and onRestoreInstanceState() called?
...oid onRestoreInstanceState (Bundle savedInstanceState)
This method is called between onStart() and onPostCreate(Bundle).
void onSaveInstanceState (Bundle outState)
If called, this method will occur after onStop() for applications targeting platforms starting with Build.VERSION_CODES.P...
How to simulate a button click using code?
...event using code in Android? I want to trigger the button click programmatically when some other event occurs.
7 Answers
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@ variables in Ruby on Rails
.....}. After this though, methods within the class access and make function calls with that variable as if it were local (i.e. "options.merge()"). Is this just bad form? Is there some other syntactic magic going in? (i.e. like making silent dup of variable, or making it 'const' so that it can't ...
Best way to select random rows PostgreSQL
..._pick
LIMIT _limit;
END
$func$ LANGUAGE plpgsql VOLATILE ROWS 1000;
Call:
SELECT * FROM f_random_sample();
SELECT * FROM f_random_sample(500, 1.05);
You could even make this generic to work for any table: Take the name of the PK column and the table as polymorphic type and use EXECUTE ... ...