大约有 40,000 项符合查询结果（耗时：0.0350秒） [XML]
MySQL select 10 random rows from 600K rows fast
... to gaps, to non-uniform with gaps.
http://jan.kneschke.de/projects/mysql/order-by-rand/
For most general case, here is how you do it:
SELECT name
FROM random AS r1 JOIN
(SELECT CEIL(RAND() *
(SELECT MAX(id)
FROM random)) AS id)
AS r2
...
Internal Error 500 Apache, but nothing in the logs?
...
Please Note: The original poster was not specifically asking about PHP. All the php centric answers make large assumptions not relevant to the actual question.
The default error log as opposed to the scripts error logs usually has the (more) specific error. often it will b...
How to select multiple files with ?
...
<form enctype='multipart/form-data' method='POST' action='submitFormTo.php'>
<input type='file' name='files[]' multiple />
<button type='submit'>Submit</button>
</form>
Make sure you have the enctype='multipart/form-data' attribute in your <form> tag, ...
How to append text to an existing file in Java?
...her use java7 try-with-resources or put the close() in a finally block, in order to make sure that the file is closed in case of exception
– Svetlin Zarev
Jan 2 '14 at 10:44
1
...
Window.open and pass parameters by post method
...').submit();
</script>
Edit:
To set the values in the form dynamically, you can do like this:
function openWindowWithPost(something, additional, misc) {
var f = document.getElementById('TheForm');
f.something.value = something;
f.more.value = additional;
f.other.value = misc;
win...
How can I make PHP display the error instead of giving me 500 Internal Server Error [duplicate]
This has never happened before. Usually it displays the error, but now it just gives me a 500 internal server error. Of course before, when it displayed the error, it was different servers. Now I'm on a new server (I have full root, so if I need to configure it somewhere in the php.ini, I can.) Or p...
How to get image height and width using java?
...56) - 2649ms, 68ms
It's obvious that some methods load the whole file in order to get dimensions while others get by just reading some header information from the image. I think these numbers may be useful when application performance is critical.
Thank you everyone for the contribution to this t...
How to encode the filename parameter of Content-Disposition header in HTTP?
...gns, at least not in front of hex digits.
attfnboth: two parameters in the order described above. Should work for most file names on most browsers, although IE8 will use the “filename” parameter.
That RFC 5987 in turn references RFC 2231, which describes the actual format. 2231 is primarily fo...
Illegal mix of collations (utf8_unicode_ci,IMPLICIT) and (utf8_general_ci,IMPLICIT) for operation '=
...ET utf8 COLLATE utf8_general_ci;
Unless you need to sort data in Unicode order, I would suggest altering all your tables to use utf8_general_ci collation, as it requires no code changes, and will speed sorts up slightly.
UPDATE: utf8mb4/utf8mb4_unicode_ci is now the preferred character set/collat...
Convert Base64 string to an image file? [duplicate]
...4_decode($image));
You can create 'public_feeds' in laravel's filesystem.php-
'public_feeds' => [
'driver' => 'local',
'root' => public_path() . '/uploads/feeds',
],
share
|
...