大约有 40,000 项符合查询结果(耗时:0.0373秒) [XML]
List all files in one directory PHP [duplicate]
...de and reviews used something like foreach(scandir($x) as $file) if ($file selection) {...}, and glob() not need the if, neither regular expressions or array_diffs for selection.
– Peter Krauss
Sep 14 '16 at 1:38
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Does the join order matter in SQL?
...t matter. The queries will return same results, as long as you change your selects from SELECT * to SELECT a.*, b.*, c.*.
For (LEFT, RIGHT or FULL) OUTER joins, yes, the order matters - and (updated) things are much more complicated.
First, outer joins are not commutative, so a LEFT JOIN b is no...
LINQ-to-SQL vs stored procedures? [closed]
... I cannot get over the performance deficit that is introduced by having to select data out of the database in order to update it (Attach() is also possible, but it's rather poopey)
– Ed James
Mar 2 '10 at 15:46
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how to customize `show processlist` in mysql?
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Newer versions of SQL support the process list in information_schema:
SELECT * FROM INFORMATION_SCHEMA.PROCESSLIST
You can ORDER BY in any way you like.
The INFORMATION_SCHEMA.PROCESSLIST table was added in MySQL 5.1.7. You can find out which version you're using with:
SELECT VERSION()
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Joining three tables using MySQL
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Simply use:
select s.name "Student", c.name "Course"
from student s, bridge b, course c
where b.sid = s.sid and b.cid = c.cid
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Change C++/CLI project to another framework than 4.0 with vs2010
... the Platform Toolset setting in the General property page. You must then select "v90" to get a proper build that targets 3.5. It is however clumsy, you must have all intermediate versions of VS installed on the machine to have that selection available.
Why you need VS2008 installed requires an e...
How to compile a 64-bit application using Visual C++ 2010 Express?
... dialog box there will be a "Configuration" drop-down menu. Make sure that selects "All Configurations." There will also be a "Platform" drop-down that will read "Win32." Finally on the right there is a "Configuration Manager" button - press it. In the dialog that comes up, find your project, hit th...
Looking for jQuery find(..) method that includes the current node
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For jQuery 1.8 and up, you can use .addBack(). It takes a selector so you don't need to filter the result:
object.find('selector').addBack('selector')
Prior to jQuery 1.8 you were stuck with .andSelf(), (now deprecated and removed) which then needed filtering:
object.find('sele...
More lines in command window
...and go to properties.
Click the Options tab.
In Command History, type or select 999 in Buffer Size, and then type or select 5 in Number of Buffers.
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Why does PostgreSQL perform sequential scan on indexed column?
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If the SELECT returns more than approximately 5-10% of all rows in the table, a sequential scan is much faster than an index scan.
This is because an index scan requires several IO operations for each row (look up the row in the ...
