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Sql Server equivalent of a COUNTIF aggregate function
...ondition (e.g. count only records where a certain column value is equal to 1).
9 Answers
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Setting JDK in Eclipse
...
146
You manage the list of available compilers in the Window -> Preferences -> Java -> In...
How do you create a yes/no boolean field in SQL server?
...
11 Answers
11
Active
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What is IP address '::1'?
...
152
::1 is the loopback address in IPv6. Think of it as the IPv6 version of 127.0.0.1.
See http:...
Truncating floats in Python
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117
First, the function, for those who just want some copy-and-paste code:
def truncate(f, n):
...
SQL Server dynamic PIVOT query?
...me,
category varchar(3),
amount money
)
insert into temp values ('1/1/2012', 'ABC', 1000.00)
insert into temp values ('2/1/2012', 'DEF', 500.00)
insert into temp values ('2/1/2012', 'GHI', 800.00)
insert into temp values ('2/10/2012', 'DEF', 700.00)
insert into temp values ('3/1/2012', 'ABC...
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Delete element in a slice
...d i is the index of the element you want to delete:
a = append(a[:i], a[i+1:]...)
... is syntax for variadic arguments in Go.
Basically, when defining a function it puts all the arguments that you pass into one slice of that type. By doing that, you can pass as many arguments as you want (for ex...
What does .SD stand for in data.table in R
...his is your data.table:
DT = data.table(x=rep(c("a","b","c"),each=2), y=c(1,3), v=1:6)
setkey(DT, y)
DT
# x y v
# 1: a 1 1
# 2: b 1 3
# 3: c 1 5
# 4: a 3 2
# 5: b 3 4
# 6: c 3 6
Doing this may help you see what .SD is:
DT[ , .SD[ , paste(x, v, sep="", collapse="_")], by=y]
# y V1
# 1...