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Python: Get the first character of the first string in a list?
How would I get the first character from the first string in a list in Python?
4 Answers
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How to atomically delete keys matching a pattern using Redis
...helped me out. Another variant if your redis keys contain quotes or other characters that mess up xargs: redis-cli KEYS "prefix:*" | xargs --delim='\n' redis-cli DEL
– overthink
Sep 16 '11 at 13:31
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Extracting the last n characters from a ruby string
To get the last n characters from a string, I assumed you could use
8 Answers
8
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LINQ to SQL Left Outer Join
...table), where-as yours matches only 0-1. To do a left outer join, you need SelectMany and DefaultIfEmpty, for example:
var query = from c in db.Customers
join o in db.Orders
on c.CustomerID equals o.CustomerID into sr
from x in sr.DefaultIfEmpty()
s...
SQL Server: converting UniqueIdentifier to string in a case statement
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I think I found the answer:
convert(nvarchar(50), RequestID)
Here's the link where I found this info:
http://msdn.microsoft.com/en-us/library/ms187928.aspx
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How to install Xcode Command Line Tools
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Xcode 5.1 and OSX 10.9. (also works with Xcode 5.1.1 + OSX 10.10)
xcode-select --install worked with version 2333, failed with version 2003. So, try xcode-select --install and if that does not work download as described below.
In early February 2014 xcode-select --install has been reporting that...
this.setState isn't merging states as I would expect
...do recursive merge.
You can use the value of the current state this.state.selected to construct a new state and then call setState() on that:
var newSelected = _.extend({}, this.state.selected);
newSelected.name = 'Barfoo';
this.setState({ selected: newSelected });
I've used function _.extend() ...
Select random row from a sqlite table
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Have a look at Selecting a Random Row from an SQLite Table
SELECT * FROM table ORDER BY RANDOM() LIMIT 1;
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How to read data when some numbers contain commas as thousand separator?
...thod using the setAs function like so:
setClass("num.with.commas")
setAs("character", "num.with.commas",
function(from) as.numeric(gsub(",", "", from) ) )
Then run read.csv like:
DF <- read.csv('your.file.here',
colClasses=c('num.with.commas','factor','character','numeric','num.w...
How much size “Null” value takes in SQL Server
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The following link claims that if the column is variable length, i.e. varchar then NULL takes 0 bytes (plus 1 byte is used to flag whether value is NULL or not):
How does SQL Server really store NULL-s
The above link, as well as the below link, claim that for fixed length columns, i.e. char(10...