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How to do a FULL OUTER JOIN in MySQL?
...e SAMPLE transcribed from this SO question you have:
with two tables t1, t2:
SELECT * FROM t1
LEFT JOIN t2 ON t1.id = t2.id
UNION
SELECT * FROM t1
RIGHT JOIN t2 ON t1.id = t2.id
The query above works for special cases where a FULL OUTER JOIN operation would not produce any duplicate rows. The ...
JavaScript pattern for multiple constructors
...
120
JavaScript doesn't have function overloading, including for methods or constructors.
If you wa...
How can I add a help method to a shell script?
...
where:
-h show this help text
-s set the seed value (default: 42)"
seed=42
while getopts ':hs:' option; do
case "$option" in
h) echo "$usage"
exit
;;
s) seed=$OPTARG
;;
:) printf "missing argument for -%s\n" "$OPTARG" >&2
echo "$usage" &g...
How do I round to the nearest 0.5?
...
208
Multiply your rating by 2, then round using Math.Round(rating, MidpointRounding.AwayFromZero),...
Show pending migrations in rails
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261
rake db:migrate:status (Rails 3 to 5) or rails db:migrate:status (Rails 5) will accomplish thi...
How can I use map and receive an index as well in Scala?
...ls.zipWithIndex.foreach{ case (e, i) => println(i+" "+e) }
0 Mary
1 had
2 a
3 little
4 lamb
From: http://www.artima.com/forums/flat.jsp?forum=283&thread=243570
You also have variations like:
for((e,i) <- List("Mary", "had", "a", "little", "lamb").zipWithIndex) println(i+" "+e)
or:
...
Quicksort: Choosing the pivot
... a random pivot minimizes the chance that you will encounter worst-case O(n2) performance (always choosing first or last would cause worst-case performance for nearly-sorted or nearly-reverse-sorted data). Choosing the middle element would also be acceptable in the majority of cases.
Also, if you ...
How to reshape data from long to wide format
...
268
Using reshape function:
reshape(dat1, idvar = "name", timevar = "numbers", direction = "wide"...
Equation (expression) parser with precedence?
...
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