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Is it a good idea to index datetime field in mysql?
...for a variety of reasons including elimination of rows between conditions: http://dev.mysql.com/doc/refman/5.0/en/mysql-indexes.html
This makes your datetime column an excellent candidate for an index if you are going to be using it in conditions frequently in queries. If your only condition is BE...
How to print register values in GDB?
...nd f (float) can be found with:
maint print reggroups
as documented at: https://sourceware.org/gdb/current/onlinedocs/gdb/Registers.html#Registers
Tips:
xmm0 ~ xmm15, are 128 bits, almost every modern machine has it, they are released in 1999.
ymm0 ~ ymm15, are 256 bits, new machine usually ha...
What is the most efficient way to store tags in a database?
... Tag_Title:text[]
For more info, see this excellent post by Josh Berkus:
http://www.databasesoup.com/2015/01/tag-all-things.html
There are more various options compared thoroughly for performance and the one suggested above is the best overall.
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Rails: Check output of path helper from console
...)
#=> "/posts/3"
app.posts_path
#=> "/posts"
app.posts_url
#=> "http://www.example.com/posts"
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A cron job for rails: best practices?
... EdiListener.process_new_messages
puts "done."
end
To execute from the command line, this is just "rake cron". This command can then be put on the operating system cron/task scheduler as desired.
Update this is quite an old question and answer! Some new info:
the heroku cron service I referen...
Kotlin: how to pass a function as parameter to another?
...
apparently this is not supported yet.
more info:
http://devnet.jetbrains.com/message/5485180#5485180
http://youtrack.jetbrains.com/issue/KT-1183
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Fetch the row which has the Max value for a column
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Differences between cookies and sessions?
...pement and am learning about JSP & Servlets . I have some knowledge of HttpSession - I have used it in some of my sample projects.
...
@Basic(optional = false) vs @Column(nullable = false) in JPA
... the specification and read up about it.
Here is what the spec has to say:
http://download.oracle.com/otndocs/jcp/persistence-2.0-fr-oth-JSpec/
Basic(optional): Whether the value of the field or property may be
null. This is a hint and is disregarded for primitive types; it may be
used in sc...
Stop UIWebView from “bouncing” vertically?
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