大约有 37,907 项符合查询结果（耗时：0.0206秒） [XML]
How do I determine whether my calculation of pi is accurate?
...putation goes bad, the digits at the end won't match.
This does typically more than double the amount of time needed (since the second algorithm is usually slower). But it's the only way to verify the computed digits once you've wandered into the uncharted territory of never-before-computed digits ...
How can I get file extensions with JavaScript?
...
|
show 7 more comments
870
...
How can I check if a Perl array contains a particular value?
... } @badparams;
if(exists($params{$someparam})) { ... }
You can also add more (unique) params to the list:
$params{$newparam} = 1;
And later get a list of (unique) params back:
@badparams = keys %params;
share
...
What are the best practices for using a GUID as a primary key, specifically regarding performance?
...5 MB)
TOTAL: 25 MB vs. 106 MB - and that's just on a single table!
Some more food for thought - excellent stuff by Kimberly Tripp - read it, read it again, digest it! It's the SQL Server indexing gospel, really.
GUIDs as PRIMARY KEY and/or clustered key
The clustered index debate continues
Ever...
Solution for “Fatal error: Maximum function nesting level of '100' reached, aborting!” in PHP
...
|
show 2 more comments
56
...
MySQL Error 1215: Cannot add foreign key constraint
... @www.jensolsson.se You are correct, if the PK includes one or more string columns then they must use the same character set and collation. In this specific case the PK was an INT so the character set of the table and/or columns was not relevant.
– Ike Walker
...
Can Objective-C switch on NSString?
Is there a more intelligent way to rewrite this?
13 Answers
13
...
HTML5 best practices; section/header/aside/article elements
...are the only ones which don’t create sections themselves
There is one more thing to sections: the following contexts (i.e. elements) create "outline boundaries". Whatever sections they contain is private to them:
the document itself with <body>
table cells with <td>
<blockquote...
Oracle SQL: Update a table with data from another table
...ng like @PaulKarr's loop -- and if there is not a unique correlation, then more than one target row may be updated for each source row.
– Andrew Leach
Dec 17 '13 at 16:12
2
...
Android AsyncTask threads limits?
...s from ever running.
For completeness, if you repeated your exercise with more than 6 tasks (e.g. 30), you will see that more than 6 will enter doInBackground as the queue will become full and the executor is pushed to create more worker threads. If you kept with the long-running task, you should s...