大约有 47,000 项符合查询结果（耗时：0.0800秒） [XML]
How to debug Lock wait timeout exceeded on MySQL?
...***
Type: InnoDB
Name:
Status:
=====================================
110514 19:44:14 INNODB MONITOR OUTPUT
=====================================
Per second averages calculated from the last 4 seconds
----------
SEMAPHORES
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OS WAIT ARRAY INFO: reservation count 9014315, signal count 780...
How can I convert a DateTime to the number of seconds since 1970?
...ateTime variable to Unix time, ie, the number of seconds since Jan 1st, 1970. It looks like a DateTime is actually implemented as the number of 'ticks' since Jan 1st, 0001.
...
Generating random whole numbers in JavaScript in a specific range?
...d it. It's a simple rule of three:
Math.random() returns a Number between 0 (inclusive) and 1 (exclusive). So we have an interval like this:
[0 .................................... 1)
Now, we'd like a number between min (inclusive) and max (exclusive):
[0 .................................... 1)...
Finding current executable's path without /proc/self/exe
...ross-platform interfaces. I've seen some projects mucking around with argv[0], but it doesn't seem entirely reliable.
13 A...
Simplest way to profile a PHP script
...
104
The PECL APD extension is used as follows:
<?php
apd_set_pprof_trace();
//rest of the scri...
What are the main uses of yield(), and how does it differ from join() and interrupt()?
...nd Java 6.
In Java 5, Thread.yield() calls the Windows API call Sleep(0). This
has the special effect of clearing the current thread's quantum and
putting it to the end of the queue for its priority level. In other
words, all runnable threads of the same priority (and those of greater
p...
Elastic Search: how to see the indexed data
...ing on your local machine), open a browser window to:
http://localhost:9200/_plugin/head/
Alternatively, you can just use curl from the command line, eg:
Check the mapping for an index:
curl -XGET 'http://127.0.0.1:9200/my_index/_mapping?pretty=1'
Get some sample docs:
curl -XGET 'http:...
“CASE” statement within “WHERE” clause in SQL Server 2008
...ery which contains "CASE" statement within "WHERE" clause. But SQL Server 2008 is giving some errors while executing it. Can anyone please help me with the correct query? Here is the query:
...
How to check whether a pandas DataFrame is empty?
...
505
You can use the attribute df.empty to check whether it's empty or not:
if df.empty:
print(...
Why does (0 < 5 < 3) return true?
...
Order of operations causes (0 < 5 < 3) to be interpreted in javascript as ((0 < 5) < 3) which produces (true < 3) and true is counted as 1, causing it to return true.
This is also why (0 < 5 < 1) returns false, (0 < 5) returns t...