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Linq: adding conditions to the where clause conditionally
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}).ToList();
This will still only result in a single call to the database, which will be effectively just as efficient as writing the query in one pass.
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Can dplyr package be used for conditional mutating?
...), 2L,
ifelse(a %in% c(0,1,3,4) | c==4, 3L, NA_integer_)))
}
BASE_fun <- function(DF) { # R v3.1.0
transform(DF, g = ifelse(a %in% c(2,5,7) | (a==1 & b==4), 2L,
ifelse(a %in% c(0,1,3,4) | c==4, 3L, NA_integer_)))
}
system.time(ans1 <- DT_fun(DT))
# user s...
Entity Framework 4 / POCO - Where to start? [closed]
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His project structure looks just like an old nHibernate based project I was working on. Cept for all the WCF jazz, which I am keen on refreshing myself on. Solid link.
– Merritt
Aug 25 '10 at 20:18
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Java EE web development, where do I start and what skills do I need? [closed]
...n learn JPA at Jakarta EE tutorial part VIII. Also, EJB3 was much improved based on lessons learnt from Spring. See also When is it necessary or convenient to use Spring or EJB3 or all of them together?
Does Java have MVC? What about JSP? Can MVC and JSP be together? JavaBeans?
You can, but that'...
Interface Builder: What are the UIView's Layout iOS 6/7 Deltas for?
...the different styles, you can change the way Interface Builder presents it based on the OS it would be running on. This is contained within the File Inspector->Interface Builder Document (1st tab on the right bar), as so:
Does this exist if I like to code my interface by hand?
Not directly, b...
Undefined reference to `sin` [duplicate]
... external references. This library supports all of the
interfaces of the Base System, as defined in Volume 1, except for the
Math Routines.
Standard C Mathematical Library
This library supports
the Base System math routines, as defined in Volume 1. The cc option
-lm is used to se...
Views vs Components in Ember.js
...your point. But I would think of a component as a black box, behaving only based on the data it gets passed in. And yes depending on what it does this could become a mess very quickly. A dedicated controller would make absolute sense, and a way it could work would be if components could become logic...
MVC 3: How to render a view without its layout page when loaded via ajax?
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couldn't you do this in a base controller, set a property in the ViewData and use that? Then the line would be Layout = ViewBag.LayoutFile.
– RPM1984
Mar 15 '11 at 22:34
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How do API Keys and Secret Keys work? Would it be secure if I have to pass my API and secret keys to
...r my credit card numbers
or password and storing that in their
own database?
Yes, though the damage someone can do with S3 seems to be limited to draining your account.
How secret do they need to be? Are
these applications that use the secret
keys storing it somehow?
At some point, y...
Data Modeling with Kafka? Topics and Partitions
...whelming Zookeeper, it is better to partition by user id, and have user id based consumers subscribe to each partition if?
– Ravindranath Akila
Sep 19 '13 at 19:41
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