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Rails - Validate Presence Of Association?
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How to branch with TortoiseHG
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edited Aug 4 '17 at 23:44
SSteve
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Remove duplicated rows using dplyr
...rame [3 x 3]
## Groups: x, y
##
## x y z
## 1 0 1 1
## 2 1 0 2
## 3 1 1 4
(In dplyr 0.2 you won't need the dummy z variable and will just be
able to write row_number() == 1)
I've also been thinking about adding a slice() function that would
work like:
df %>% group_by(x, y) %>% slice(fro...
Convert varchar to uniqueidentifier in SQL Server
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SELECT CAST(
SUBSTRING(@uuid, 1, 8) + '-' + SUBSTRING(@uuid, 9, 4) + '-' + SUBSTRING(@uuid, 13, 4) + '-' +
SUBSTRING(@uuid, 17, 4) + '-' + SUBSTRING(@uuid, 21, 12)
AS UNIQUEIDENTIFIER)
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Finding the index of elements based on a condition using python list comprehension
... Mike GrahamMike Graham
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String Concatenation using '+' operator
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143
It doesn't - the C# compiler does :)
So this code:
string x = "hello";
string y = "there";
st...
Set default value of an integer column SQLite
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234
Use the SQLite keyword default
db.execSQL("CREATE TABLE " + DATABASE_TABLE + " ("
+ KEY_RO...