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How to create a MySQL hierarchical recursive query
...cte
on p.parent_id = cte.id
)
select * from cte;
The value specified in parent_id = 19 should be set to the id of the parent you want to select all the descendants of.
MySQL 5.x
For MySQL versions that do not support Common Table Expressions (up to version 5.7), you would achieve this ...
PHP function to make slug (URL string)
...
Instead of a lengthy replace, try this one:
public static function slugify($text)
{
// replace non letter or digits by -
$text = preg_replace('~[^\pL\d]+~u', '-', $text);
// transliterate
$text = iconv('utf-8', 'us-ascii//TRANSLIT', $text);
// remove unwanted characters
$text = pre...
Is there a bash command which counts files?
... bash:
ls -1q log* | wc -l
ls -1q will give you one line per file, even if they contain whitespace or special characters such as newlines.
The output is piped to wc -l, which counts the number of lines.
share
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Javascript !instanceof If Statement
...
Enclose in parentheses and negate on the outside.
if(!(obj instanceof Array)) {
//...
}
In this case, the order of precedence is important (https://developer.mozilla.org/en-US/docs/JavaScript/Reference/Operators/Operator_Precedence). The ! operator precedes the instanc...
Using std Namespace
There seem to be different views on using 'using' with respect to the std namespace.
15 Answers
...
Stop setInterval call in JavaScript
... How can you start it again after stopping with 'clearInterval()'? If I try to restart it I get 2x the setInterval running.
– Dan
Apr 2 '12 at 15:37
9
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Accessing elements of Python dictionary by index
...
Like, for example, if you had a dictionary of unknown depth, e.g, a nested dictionary, and you have element "n" at an unknown depth, stored in an unknown element.
– Ethan Bierlein
May 13 '15 at 12:27
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How to add elements of a Java8 stream into an existing List
...nswer is no, at least, not in general, you shouldn't use a Collector to modify an existing collection.
The reason is that collectors are designed to support parallelism, even over collections that aren't thread-safe. The way they do this is to have each thread operate independently on its own colle...
Correct way to use StringBuilder in SQL
...usually) is to reduce memory churn rather than total memory used, to make life a bit easier on the garbage collector.
Will that take memory equal to using String like below?
No, it'll cause more memory churn than just the straight concat you quoted. (Until/unless the JVM optimizer sees that th...
Capture characters from standard input without waiting for enter to be pressed
... manpage). See Curses at Wikipedia.
I would recommend you to use curses if you aim for cross platform compatibility. That said, I'm sure there are functions that you can use to switch off line buffering (I believe that's called "raw mode", as opposed to "cooked mode" - look into man stty). Curses...