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Will the Garbage Collector call IDisposable.Dispose for me?
...xpensive (since your threads may be suspended during the operation).
This means that if you do something like this:
~MyClass() { }
Your object, no matter what, will live to Generation 2. This is because the GC has no way of calling the finalizer during garbage collection. So objects that have to...
Update or Insert (multiple rows and columns) from subquery in PostgreSQL
... as col2, t3.foobar as col3
FROM table2 t2 INNER JOIN table3 t3 ON t2.id = t3.t2_id
WHERE t2.created_at > '2016-01-01'
) AS subquery
WHERE table1.id = subquery.col1;
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What is going wrong when Visual Studio tells me “xcopy exited with code 4”
...
Xcopy exit code 4 means "Initialization error occurred. There is not enough memory or disk space, or you entered an invalid drive name or invalid syntax on the command line."
It looks like Visual Studio is supplying invalid arguments to xcopy...
How to filter Pandas dataframe using 'in' and 'not in' like in SQL
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Series.isin accepts various types as inputs. The following are all valid ways of getting what you want:
df['countries'].isin(c1)
0 False
1 True
2 False
3 False
4 True
Name: countries, dtype: bool
# `in` operation
df[df['countries'].isin(c1)]
countries
1 UK
4 Ch...
Static linking vs dynamic linking
...er is insufficiently flexible there is a risk of DLL hell.
Dynamic linking means that bug fixes and upgrades to libraries propagate to improve your product without requiring you to ship anything.
Plugins always call for dynamic linking.
Static linking, means that you can know the code will run in ve...
Converting integer to binary in python
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The first 0 means the 0th argument to format. After the colon is the formatting, the second 0 means zero fill to 8 spaces and b for binary
– jamylak
May 2 '12 at 9:39
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Equals(=) vs. LIKE
...al values is implementation-dependent.
(Emphasis added.)
What does this mean? It means that when comparing strings, the = operator is just a thin wrapper around the current collation. A collation is a library that has various rules for comparing strings. Here's an example of a binary collation fr...
Lists: Count vs Count() [duplicate]
... case” for Lists that allows it to use the list’s Count property, this means the Count() method is only a little slower than the Count property.
It in unlikely you will be able to tell the difference in speed in most applications.
So if you know you are dealing with a List use the Count proper...
Printing the last column of a line in a file
...t is shown, when there are enough lines or end of file is reached. tail -f means wait for more input, but there are no more lines in file and so the pipe to grep is never closed.
If you omit -f from tail the output is shown immediately:
tail file | grep A1 | awk '{print $NF}'
@EdMorton is righ...
Safe String to BigDecimal conversion
...e it looks very odd when people have pointed out why your original answer didn't make any sense. :-)
– T.J. Crowder
Sep 20 '10 at 15:03
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