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Best practices for SQL varchar column length [closed]
...archar column to an existing table, I am wondering one thing: what is the best value for the length .
8 Answers
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How can I run a program from a batch file without leaving the console open after the program starts?
... > 1 then
sargs = " "
for k = 1 to num - 1
anArg = args.Item(k)
sargs = sargs & anArg & " "
next
end if
Set WshShell = WScript.CreateObject("WScript.Shell")
WshShell.Run """" & WScript.Arguments(0) & """" & sargs, 0, False
...
Read-only list or unmodifiable list in .NET 4.0
...<T> for example.
It is similar to IReadOnlyCollection and adds an Item indexer property.
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Find element's index in pandas Series
...7]: s = Series(randint(0,10,10000))
In [9]: %timeit s[s == 5]
1000 loops, best of 3: 203 µs per loop
In [12]: i = Index(s)
In [13]: %timeit i.get_loc(5)
1000 loops, best of 3: 226 µs per loop
As Viktor points out, there is a one-time creation overhead to creating an index (its incurred when y...
How does MySQL process ORDER BY and LIMIT in a query?
...have any measurable impact on performance since it is limited to 10 rows / items only :-). In general sorting an in-memory table (which a sub-select is producing) is very fast and barely measurable unless you have millions of rows or the DBMS is paging the result set to disk since it does not fit ...
Check whether an array is a subset of another
...turning an IEnumerable not a Collection. It only emits all of the possible items if you iterate completely over it, for example by ToArray () or ToList () or use foreach without breaking inside. Search for linq deferred execution to read more about that concept.
– abto
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Different return values the first and second time with Moq
...the Dequeue. The way the sample is written it will always return the first item in the queue repeatedly, because the dequeue is evaluated at time of setup.
– Jason Coyne
Aug 8 '14 at 15:43
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How do I return to an older version of our code in Subversion?
...f the old copy you want.
Get your current revision with:
svn info --show-item revision
# or
svn log
Or to check older versions of your project, use:
svn update -r <earlier_revision_number>
until you find the right revision number.
Note down the good revision number (assuming 123 for exa...
Flatten an Array of Arrays in Swift
...n (flattening a 2D array to 1D). compactMap is explicitly for removing nil items from a sequence, as a variant of flatMap once did.
– Jim Dovey
Aug 8 '19 at 22:29
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What are best practices for validating email addresses on iOS 2.0
...ill never verify it with any level of accuracy with a regex alone, so it's best not to piss of users and lose sign ups because of an unnecessarily strict regex.
– Sami Samhuri
Sep 13 '11 at 16:35
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