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What's the fastest way to merge/join data.frames in R?
..., in fact, they are placed on tables which were overwritten before the sql select ever runs and that, in part, accounts for why its so slow. The idea of sqldf is that the data frames in your R session constitute the data base, not the tables in sqlite. Thus each time the code refers to an unqualif...
What Java ORM do you prefer, and why? [closed]
...ay give jOOQ a try. You'll love it! :-)
Check out this example SQL:
// Select authors with books that are sold out
SELECT *
FROM T_AUTHOR a
WHERE EXISTS (SELECT 1
FROM T_BOOK
WHERE T_BOOK.STATUS = 'SOLD OUT'
AND T_BOOK.AUTHOR_ID ...
jQuery Validate Plugin - Trigger validation of single field
...he API:
var validator = $( "#myform" ).validate();
validator.element( "#myselect" );
.valid() validates the entire form, as others have pointed out. The API says:
Checks whether the selected form is valid or whether all selected
elements are valid.
...
How do I declare an array of weak references in Swift?
...gt;.weakObjects()
NSHashTable Class Reference
Available in OS X v10.5 and later.
Available in iOS 6.0 and later.
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Flexbox: center horizontally and vertically
How to center div horizontally, and vertically within the container using flexbox. In below example, I want each number below each other (in rows), which are centered horizontally.
...
Missing include “bits/c++config.h” when cross compiling 64 bit program on 32 bit in Ubuntu
I am running the 32bit version of Ubuntu 10.10 and trying to cross compile to a 64 bit target. Based on my research, I have installed the g++-multilib package.
...
Manually adding a Userscript to Google Chrome
...ey extension.
This will allow you to easily install Greasemonkey scripts, and to easily manage them. Also it makes it easier to install userscripts directly from sites like OpenUserJS, MonkeyGuts, etc.
Finally, it unlocks most all of the GM functionality that you don't get by installing a GM scri...
How to insert a value that contains an apostrophe (single quote)?
... 'O''Brien')
/\
right here
The same applies to SELECT queries:
SELECT First, Last FROM Person WHERE Last = 'O''Brien'
The apostrophe, or single quote, is a special character in SQL that specifies the beginning and end of string data. This means that to use it as part...
Cannot convert lambda expression to type 'string' because it is not a delegate type [duplicate]
...ID == Value
orderby q.RowID descending
select q).FirstOrDefault();
Errors:
Error 241 Cannot convert lambda expression to type 'string' because it is not a delegate type
Error 242 Delegate 'System.Func<..>' does not take 1 arguments
Error 243 The name 'Valu...
Keyboard shortcuts are not active in Visual Studio with Resharper installed
...ou can look at the Visual Studio Integration options for ReSharper by...
Select ReSharper > Options... from the Visual Studio menu
Select the Visual Studio Integration item on the Options window
The bottom of the page gives instructions on how to reset the keyboard scheme.
If that doesn't w...