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Count with IF condition in MySQL query
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edited Aug 7 '19 at 14:25
ElChiniNet
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What is ASP.NET Identity's IUserSecurityStampStore interface?
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+50
This is meant to represent the current snapshot of your user's credentials. So if nothing changes, the stamp will stay the same. Bu...
Booleans, conditional operators and autoboxing
...ing of 3rd operand to Boolean)
See Java Language Specification, section 15.25 Conditional Operator ? :
For E1, the types of the 2nd and 3rd operands are Boolean and boolean respectively, so this clause applies:
If one of the second and third operands is of type boolean and the type of the ot...
Cleanest and most Pythonic way to get tomorrow's date?
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252
datetime.date.today() + datetime.timedelta(days=1) should do the trick
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Git stash twice
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stash@{0}: WIP on dev: 1f6f8bb Commit message A
stash@{1}: WIP on master: 50cf63b Commit message B
If you made two stashes, then just call git stash pop twice. As opposed to git stash apply, pop applies and removes the latest stash.
You can also reference a specific stash, e.g.
git stash show s...
Difference between exit(0) and exit(1) in Python
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5 Answers
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bool operator ++ and --
...it's own. Even with char as the type used and CHAR_BITS something low like 5, that's 32 times before this doesn't work any more (that's still argument enough for it being a bad practice, I'm not defending the practice, just explaining why it works) for a 32-bit int we of course would have to use ++ ...
What does .SD stand for in data.table in R
...=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: 1 a1_b3_c5
# 2: 3 a2_b4_c6
Basically, the by=y statement breaks the ...