大约有 47,000 项符合查询结果（耗时：0.0385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
...
Row Offset in SQL Server
...2005+
SELECT col1, col2
FROM (
SELECT col1, col2, ROW_NUMBER() OVER (ORDER BY ID) AS RowNum
FROM MyTable
) AS MyDerivedTable
WHERE MyDerivedTable.RowNum BETWEEN @startRow AND @endRow
SQL Server 2000
Efficiently Paging Through Large Result Sets in SQL Server 2000
A More Efficient Method...
“To Do” list before publishing Android app to market [closed]
...
Really useful but keep in mind that, In order to provide a proper UX experience, you better have valid reasons to go full screen. Like if you want user to focus on one single element and remove all other distractions on the way.
– whizzkid
...
Detach (move) subdirectory into separate Git repository
... from 60M to ~300K. Note that I needed to run both of these commands to in order to get the size reduction.
– saltycrane
Nov 17 '11 at 21:18
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When to Redis? When to MongoDB? [closed]
...performance is not that great and can't be compared to Redis.
Use Redis in order to speed up your existing application.
Redis can be easily integrated as a LRU cache. It is very uncommon to use Redis as a standalone database system (some people prefer referring to it as a "key-value"-store). Websit...
Sort an Array by keys based on another Array?
...e this? How would you go about writing a function? Here is an example. The order is the most important thing.
15 Answers
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How to set a Default Route (To an Area) in MVC
...
);
}
in Application_Start(), make sure to use the following order;
protected void Application_Start()
{
AreaRegistration.RegisterAllAreas();
RegisterRoutes(RouteTable.Routes);
}
in you area registration, use
public override void RegisterArea(AreaReg...
javac is not recognized as an internal or external command, operable program or batch file [closed]
...of conflicts. (For instance, if you have JRE 8 and JDK 11 in PATH, in that order, then javac will invoke the Java 11 compiler, which will create version 55 .class files, but java will invoke the Java 8 JVM, which only supports up to version 52, and you will experience unsupported version errors and ...
How do I check if there are duplicates in a flat list?
...s I had tried your_list != list(set(your_list)) which will not work as the order of the elements will change. Using len is a good way to solve this problem
– igniteflow
May 31 '12 at 14:37
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Rails 3: Get Random Record
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Thing.first(:order => "RANDOM()") # For MySQL :order => "RAND()", - thanx, @DanSingerman
# Rails 3
Thing.order("RANDOM()").first
or
Thing.first(:offset => rand(Thing.count))
# Rails 3
Thing.offset(rand(Thing.count)).first
Ac...