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How can I check a C# variable is an empty string “” or null? [duplicate]
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Are we to assume that this conversion of stringVar to a cast object returns empty string for both null and empty string assigned to the stringVar variable, but converting the same stringVar without the cast returns null and empty string instead? Im just trying to find out all the ...
SQL query to get all values a enum can have
...ove query will be myenum. Depending on what you are doing, you may need to cast to text. e.g.
SELECT unnest(enum_range(NULL::myenum))::text
If you want to specify the column name, you can append AS my_col_name.
Credit to Justin Ohms for pointing out some additional tips, which I incorporated...
mkdir -p functionality in Python [duplicate]
...ution other than a system call. I am sure the code is less than 20 lines, and I am wondering if someone has already written it?
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Append to a file in Go
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@SridharRatnakumar: see another comment and man umask. With typical umask of 022, you'll get typical permissions: 0666 & ~022 = 0644 = rw-r--r--
– akavel
Oct 22 '13 at 19:52
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Most efficient way to check for DBNull and then assign to a variable?
...ert(Of Integer)(oRow("Value")), iDefault)
oSomeObject.StringMember = If(TryCast(oRow("Name"), String), sDefault)
Function TryConvert(Of T As Structure)(ByVal obj As Object) As T?
If TypeOf obj Is T Then
Return New T?(DirectCast(obj, T))
Else
Return Nothing
End If
End Fun...
Lua string to int
...Integer(number)
return math.floor(tonumber(number) or error("Could not cast '" .. tostring(number) .. "' to number.'"))
end
In which case you explicitly convert the string (or really, whatever it is) into a number, and then truncate the number like an (int) cast would do in Java.
Edit: This ...
Python subprocess/Popen with a modified environment
I believe that running an external command with a slightly modified environment is a very common case. That's how I tend to do it:
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Copy multiple files in Python
...in one directory to another directory using Python.
I have the source path and the destination path as string.
6 Answers
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SQL select only rows with max value on a column [duplicate]
...'s how it looks with the above example, written in SQL
SELECT id,
CAST(SUBSTRING(max(packed_col) FROM 2 FOR 6) AS float) as max_rev,
SUBSTRING(max(packed_col) FROM 11) AS content_for_max_rev
FROM (SELECT id,
CAST(1000 + rev + .001 as CHAR) || '---' || CAST(content AS char) ...
Bundling data files with PyInstaller (--onefile)
...ying to build a one-file EXE with PyInstaller which is to include an image and an icon. I cannot for the life of me get it to work with --onefile .
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