大约有 15,900 项符合查询结果（耗时：0.0625秒） [XML]
How do I (or can I) SELECT DISTINCT on multiple columns?
... the performance of the currently accepted answer by factor 10 - 15 (in my tests on PostgreSQL 8.4 and 9.1).
But this is still far from optimal. Use a NOT EXISTS (anti-)semi-join for even better performance. EXISTS is standard SQL, has been around forever (at least since PostgreSQL 7.2, long before...
Remove HTML Tags in Javascript with Regex
...0% of the time:
var regex = /(<([^>]+)>)/ig
, body = "<p>test</p>"
, result = body.replace(regex, "");
console.log(result);
If you're willing to use a library such as jQuery, you could simply do this:
console.log($('<p>test</p>').text());
...
Java, List only subdirectories from a directory, not files
...rn true. In order to see if the child is a subdirectory or not you need to test that child.
File file = new File("/path/to/directory");
String[] directories = file.list(new FilenameFilter() {
@Override
public boolean accept(File current, String name) {
return new File(current, name).isDirec...
Haskell offline documentation?
...tiple databases into one
convert Convert an input file to a database
test Run tests
dump Dump sections of a database to stdout
rank Generate ranking information
log Analyse log files
Common flags:
-? --help Display help message
-V --version Print version in...
How do I check if a column is empty or null in MySQL?
... '' = ' ' works in SQLServer but not in SQLite, as far as I can tell, from testing it now.
– Magne
Oct 3 '17 at 9:59
add a comment
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How do I prevent the modification of a private field in a class?
...ll never change
Here is a simple example of how to use it:
public class Test
{
private String[] arr = new String[]{"1","2"};
public ImmutableList<String> getArr()
{
return ImmutableList.copyOf(arr);
}
}
...
jQuery Determine if a matched class has a given id
...that lets your determine whether an element has certain qualities. You can test a jQuery collection against a string selector, an HTML Element, or another jQuery object. In this case, we'll just check it against a string selector:
$(".bar:first").is("#foo"); // TRUE if first '.bar' in document is a...
Iterate over each line in a string in PHP
...lse) {
# do something with $line
$line = strtok( $separator );
}
Testing the performance, I iterated 100 times over a test file with 17 thousand lines: preg_split took 27.7 seconds, whereas strtok took 1.4 seconds.
Note that though the $separator is defined as "\r\n", strtok will separate...
Display numbers with ordinal suffix in PHP
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@HafezDivandari - are you sure? Just tested with 7.1.19 and seems to work fine
– Iacopo
Dec 5 '18 at 9:35
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Stack Memory vs Heap Memory [duplicate]
... case of C++, the code is not run in either the stack or the heap. You can test what happens if you run out of heap memory by repeatingly calling new to allocate memory in a loop without calling delete to free it it. But make a system backup before doing this.
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