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How to detect the OS from a Bash script?
I would like to keep my .bashrc and .bash_login files in version control so that I can use them between all the computers I use. The problem is I have some OS specific aliases so I was looking for a way to determine if the script is running on Mac OS X, Linux or Cygwin .
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Does the Java &= operator apply & or &&?
...So a &= b; is equivalent to a = a & b;.
(In some usages, the type-casting makes a difference to the result, but in this one b has to be boolean and the type-cast does nothing.)
And, for the record, a &&= b; is not valid Java. There is no &&= operator.
In practice, there...
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...
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 ...
How do I check if a SQL Server text column is empty?
...he added overhead of calling SQL Functions like DataLength(), IsNull(), or Cast(). Maybe the generated query plan is the same (I didn't check); still I find this to be a far cleaner approach.
– MikeTeeVee
Nov 13 '19 at 11:49
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How can I create directories recursively? [duplicate]
...s.makedirs is what you need. For chmod or chown you'll have to use os.walk and use it on every file/dir yourself.
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What to do on TransactionTooLargeException
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I encountered this issue, and I found that when there huge amount of data getting exchanged between a service and an application,(This involves transferring lots of thumbnails). Actually data size was around 500kb, and the IPC transaction buffer size...
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...
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) ...
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 ...