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Q：每次修改组件/代码块之后，AI伴侣如何及时更新？
连接菜单 -> 刷新AI伴侣屏幕：
界面有更新会自动刷新；代码块有更新需要点上面菜单手动刷新后立马生效。
千万不要傻乎乎的每次断开连接，再...
How do I remove a MySQL database?
...from my last question that a problem caused some more problems, Reading MySQL manuals in MySQL monitor?
6 Answers
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PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
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To answer your concerns:
MySQL >= 5.1.17 (or >= 5.1.21 for the PREPARE and EXECUTE statements) can use prepared statements in the query cache. So your version of MySQL+PHP can use prepared statements with the query cache. However, make careful no...
How big can a MySQL database get before performance starts to degrade
At what point does a MySQL database start to lose performance?
15 Answers
15
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What's the difference between RANK() and DENSE_RANK() functions in oracle?
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Error :SQL Error: ORA-00923: FROM keyword not found where expected
– zloctb
Aug 18 '15 at 8:07
add a commen...
关于php的socket初探 - 更多技术 - 清泛网 - 专注C/C++及内核技术
...来看以不同io模型来实现一个socket（io） server的功能
1、使用 accept 阻塞的古老模型：属于同步阻塞 IO 模型，代码如下：
socket_server.php
<?php
/**
* SocketServer Class
* By James.Huang <shagoo#gmail.com>
**/
set_time_limit(0);
class Socket...
django test app error - Got an error creating the test database: permission denied to create databas
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Though the OP used postgresql, if you are using mysql you will have the same error. You can fix it for mysql with: => GRANT ALL ON *.* TO django@localhost; I originally tried to only GRANT CREATE... but then could not SELECT or DROP the created d...
How to list active / open connections in Oracle?
...lect * from FROM v$session Error at Command Line:1 Column:14 Error report: SQL Error: ORA-00903: invalid table name 00903. 00000 - "invalid table name" *Cause: *Action:
– pistacchio
Jun 25 '09 at 10:22
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Add unique constraint to combination of two columns
...can often be better to check for this violation first, before just letting SQL Server try to insert the row and returning an exception (exceptions are expensive).
http://www.sqlperformance.com/2012/08/t-sql-queries/error-handling
http://www.mssqltips.com/sqlservertip/2632/checking-for-potential-co...
MySQL: How to copy rows, but change a few fields?
...s or something and you don't want to type them all, then you could write a SQL statement to build your SQL statement :). The way you would do it would be to use the information_schema to get the column names for the table. But that's really overkill, I'd just type out the column names.
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