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How do I find a “gap” in running counter with SQL?
...e( name ) select name from artificial_range;
-- you now have eight rows
--etc.
insert into artificial_range( name ) select name from artificial_range;
-- you now have 1024 rows, with ids 1-1024
Then,
select a.id from artificial_range a
where not exists ( select * from your_table b
where b.co...
Returning a value from thread?
...thod - you don't normally "return" a value.
However, if you're trying to fetch a value back from the results of some processing, you have many options, the two main ones being:
You can synchronize a shared piece of data, and set it appropriately.
You can also pass the data back in some form of ...
What is the difference between compare() and compareTo()?
...m as an object that you can pass as a parameter, save in a data structure, etc.
If your class objects have one natural sorting order, you may not need compare().
Summary from http://www.digizol.com/2008/07/java-sorting-comparator-vs-comparable.html
Comparable
A comparable object is capable o...
What is the difference between the | and || or operators?
... know what that is. It's used in conditional statements such as if, while, etc.
condition1 || condition2
Evaluates to true if either condition1 OR condition2 is true.
| is the bitwise OR operator. It's used to operate on two numbers. You look at each bit of each number individually and, if one o...
How to draw a circle with text in the middle?
...e circle plus vertical centering */
.circle_text
{
/* change font/size/etc here */
font: 11px "Tahoma", Arial, Serif;
text-align : center;
/* vertical centering technique */
position : relative;
top : 50%;
transform : translateY(-50%);
}
<div class="circle_container">
&...
Boolean vs boolean in Java
... in Compilation and Runtime (a bit far going but almost as instanceof vs. getClass()).
Finally, autoboxing is slower than primitives
Note the fact that Java can do autoboxing is just a "syntactic sugar". It does not speed up anything, just allows you to write less code. That's it. Casting and wra...
How do I write unit tests in PHP? [closed]
...ble. In case you need help to set it up, feel free to ask (but provide OS, etc.).
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How is Python's List Implemented?
...size;
/* Vector of pointers to list elements. list[0] is ob_item[0], etc. */
PyObject **ob_item;
/* ob_item contains space for 'allocated' elements. The number
* currently in use is ob_size.
* Invariants:
* 0 <= ob_size <= allocated
* len(list) == ob...
Download large file in python with requests
... copyfileobj gets you to ~40MB/s. Curl downloads (same machines, same url, etc) with ~50-55 MB/s.
– visoft
Jul 12 '17 at 7:05
26
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How do I center floated elements?
...gination.
Strengths:
cross-browser for any elements (blocks, list-items etc.)
simplicity
Weaknesses:
it works only when all floating elements are in one line (which is usually ok for menus but not for galleries).
@arnaud576875 Using inline-block elements will work great (cross-browser) in ...