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Storing sex (gender) in database
...nge of Values
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TinyINT 1 255 (zero to 255)
INT 4 - 2,147,483,648 to 2,147,483,647
BIT 1 (2 if 9+ columns) 2 (0 and 1)
CHAR(1) 1 26 if case insensitive, 52 otherwise
The B...
How to find all occurrences of an element in a list?
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16 Answers
16
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How do I specify multiple targets in my podfile for my Xcode project?
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CocoaPods 1.0 has changed the syntax for this. It now looks like this:
def shared_pods
pod 'SSKeychain', '~> 0.1.4'
pod 'INAppStoreWindow', :head
pod 'AFNetworking', '1.1.0'
pod 'Reachability', '~> 3.1.0'
po...
Can the Unix list command 'ls' output numerical chmod permissions?
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it almost can ..
ls -l | awk '{k=0;for(i=0;i<=8;i++)k+=((substr($1,i+2,1)~/[rwx]/) \
*2^(8-i));if(k)printf("%0o ",k);print}'
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Setting JDK in Eclipse
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146
You manage the list of available compilers in the Window -> Preferences -> Java -> In...
Ruby: require vs require_relative - best practice to workaround running in both Ruby =1.
... want to require a relative file in Ruby and I want it to work in both 1.8.x and >=1.9.2?
11 Answers
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How do I get Month and Date of JavaScript in 2 digit format?
...tDate()).slice(-2)
for the date, and similar:
("0" + (this.getMonth() + 1)).slice(-2)
for the month.
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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...
How to sleep for five seconds in a batch file/cmd [duplicate]
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One hack is to (mis)use the ping command:
ping 127.0.0.1 -n 6 > nul
Explanation:
ping is a system utility that sends ping requests. ping is available on all versions of Windows.
127.0.0.1 is the IP address of localhost. This IP address is guaranteed to always resol...