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Why does X[Y] join of data.tables not allow a full outer join, or a left join?
... rows of X[Y] and Y[X] usually differ, whereas the number of rows returned by merge(X,Y) and merge(Y,X) is the same.
BUT that misses the main point. Most tasks require something to be done on the
data after a join or merge. Why merge all the columns of data, only to
use a small subset of th...
What is the difference between a strongly typed language and a statically typed language?
...tatically typed language has a type system that is checked at compile time by the implementation (a compiler or interpreter). The type check rejects some programs, and programs that pass the check usually come with some guarantees; for example, the compiler guarantees not to use integer arithmetic ...
undefined reference to `WinMain@16'
... 00000003 (Windows CUI)
C:\test> _
This means that the linker by default produced a console subsystem executable. The subsystem value in the file header tells Windows what services the program requires. In this case, with console system, that the program requires a console window.
This...
How to match, but not capture, part of a regex?
...ut this regular expression matches only apple or banana if it’s preceded by 123- and followed by -456, or it matches the empty string if it’s preceded by 123- and followed by 456.
|Lookaround | Name | What it Does |
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HTTP vs HTTPS performance
...rience, servers that are heavy on dynamic content tend to be impacted less by HTTPS because the time spent encrypting (SSL-overhead) is insignificant compared to content generation time.
Servers that are heavy on serving a fairly small set of static pages that can easily be cached in memory suffer ...
How do I return rows with a specific value first?
...le, DB2, and many other database systems, this is what you can use:
ORDER BY CASE WHEN city = 'New York' THEN 1 ELSE 2 END, city
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Visualizing branch topology in Git
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See also answer by Andrew regarding --simplify-by-decoration option.
– ruvim
Nov 14 '16 at 23:24
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How to determine day of week by passing specific date?
...a.util.Calendar, and java.text.SimpleDateFormat are now legacy, supplanted by the java.time classes built into Java 8 & Java 9. See Tutorial by Oracle.
– Basil Bourque
Nov 3 '17 at 21:25
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How can I use optional parameters in a T-SQL stored procedure?
...a, your schema, and your actual usage:
Dynamic Search Conditions in T-SQL by by Erland Sommarskog
The Curse and Blessings of Dynamic SQL by Erland Sommarskog
If you have the proper SQL Server 2008 version (SQL 2008 SP1 CU5 (10.0.2746) and later), you can use this little trick to actually use an i...
How to Sync iPhone Core Data with web server, and then push to other devices? [closed]
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I suggest carefully reading and implementing the sync strategy discussed by Dan Grover at iPhone 2009 conference, available here as a pdf document.
This is a viable solution and is not that difficult to implement (Dan implemented this in several of its applications), overlapping the solution desc...