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Func vs. Action vs. Predicate [duplicate]
...s probably most commonly used in LINQ - for example in projections:
list.Select(x => x.SomeProperty)
or filtering:
list.Where(x => x.SomeValue == someOtherValue)
or key selection:
list.Join(otherList, x => x.FirstKey, y => y.SecondKey, ...)
Action is more commonly used for th...
MySQL stored procedure vs function, which would I use when?
...d procedures with ordinary SQL, whilst with stored function you can.
e.g. SELECT get_foo(myColumn) FROM mytable is not valid if get_foo() is a procedure, but you can do that if get_foo() is a function. The price is that functions have more limitations than a procedure.
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Compare two data.frames to find the rows in data.frame 1 that are not present in data.frame 2
...ata.frame(a = 1:3, b=letters[1:3])
require(sqldf)
a1NotIna2 <- sqldf('SELECT * FROM a1 EXCEPT SELECT * FROM a2')
And the rows which are in both data frames:
a1Ina2 <- sqldf('SELECT * FROM a1 INTERSECT SELECT * FROM a2')
The new version of dplyr has a function, anti_join, for exactly the...
How to debug Spring Boot application with Eclipse?
...dd that Remote Java Application configuration in Run/Debug configurations, select the port/address you defined when starting your app, and then you are free to debug.
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How do I search within an array of hashes by hash values in ruby?
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You're looking for Enumerable#select (also called find_all):
@fathers.select {|father| father["age"] > 35 }
# => [ { "age" => 40, "father" => "Bob" },
# { "age" => 50, "father" => "Batman" } ]
Per the documentation, it "returns a...
CSS Selector “(A or B) and C”?
...rmit groupings. It's essentially the lowest-precedence logical operator in selectors, so you must use .a.c,.b.c.
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Any good, visual HTML5 Editor or IDE? [closed]
...E Developers" Latest Stable Version Download Google Plugin for Eclipse.zip Select your download according to your Eclipse Version After Downloading (don't Unzip) Open Eclipse Help > Install New Software > Add > Archive > Select the Downloaded Plug-in.zip
in the field "Name" enter "Google...
Flask SQLAlchemy query, specify column names
How do I specify the column that I want in my query using a model (it selects all columns by default)? I know how to do this with the sqlalchmey session: session.query(self.col1) , but how do I do it with with models? I can't do SomeModel.query() . Is there a way?
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jQuery: Selecting by class and input type
I would like to select a set of elements that are both of a certain input type (say, a checkbox) and have a certain class using jQuery. However, when I try the following:
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Core dump file analysis [duplicate]
...ber (replacing number with the corresponding number in the stack trace) to select a particular stack frame.
You can then use list to see code around that function, and info locals to see the local variables. You can also use print name_of_variable (replacing "name_of_variable" with a variable name)...