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Software Design vs. Software Architecture [closed]
..., some component’s internal design decisions, like- choice of algorithm, selection of data structure etc.
Any design decision, which isn’t visible outside of its component boundary is a component’s internal design and is non-architectural. These are the design decisions a system architect woul...
What does .SD stand for in data.table in R
...iping can be beautiful
library(Lahman)
Teams = as.data.table(Teams)
# *I'm selectively suppressing the printed output of tables here*
Teams
Pitching = as.data.table(Pitching)
# subset for conciseness
Pitching = Pitching[ , .(playerID, yearID, teamID, W, L, G, ERA)]
Pitching
Naked .SD
To illustrat...
What is sharding and why is it important?
... a DBMS for which the locality is quite restricted (say, a user only fires selects with a 'where username = $my_username') it makes sense to put all the usernames starting with A-M on one server and all from N-Z on the other. By this you get near linear scaling for some queries.
Long story short: S...
Factory Pattern. When to use factory methods?
...or further application development, then factory method is one of the best selections for creation pattern. Reason behind; We know that when to create an object of required functionality(s) but type of object will remain undecided or it will be decided ob dynamic parameters being passed.
Now the po...
What is the difference between “expose” and “publish” in Docker?
...col are optional, if not a public port is specified, a random port will be selected on host by docker to expose the specified container port on Dockerfile.
A good pratice is do not specify public port, because it limits only one container per host ( a second container will throw a port already in u...
Finding a branch point with Git?
...ed from master):
or here (as viewed from topic):
in both cases, I've selected the commit that is B in my graph. Once you click on it, its full SHA is presented in a text input field just below the graph.
2. visually, but from the terminal:
git log --graph --oneline --all
(Edit/side-note:...
Many-to-many relationship with the same model in rails?
...ails generates in the log file. You'll find something like the following:
SELECT * FROM "posts"
INNER JOIN "post_connections" ON "posts".id = "post_connections".post_b_id
WHERE ("post_connections".post_a_id = 1 )
To make the association bi-directional, we'd have to find a way to make Rails OR the...
Where is Erlang used and why? [closed]
...; none.
That's 5 different versions of the access function.
Erlang will select the most appropriate version given the arguments received. (Config is a structure of type #config which has a type attribute).
That means it is very easy and much clearer than chaining if/else or switch/case to make b...
Any reason why scala does not explicitly support dependent types?
...ndent types is via path-dependent types. These allow a type to depend on a selector path through an object- (ie. value-) graph like so,
scala> class Foo { class Bar }
defined class Foo
scala> val foo1 = new Foo
foo1: Foo = Foo@24bc0658
scala> val foo2 = new Foo
foo2: Foo = Foo@6f7f757
s...
How to re-sync the Mysql DB if Master and slave have different database incase of Mysql replication?
...ysqldump fare with large databases in terms of performance? Any way to use SELECT INTO OUTFILE and LOAD DATA smoothly in your suggested process? (Since they generally perform faster)
– Ifedi Okonkwo
Jul 12 '16 at 19:35
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