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How do I check if a column is empty or null in MySQL?
...e_col = ' ' (one space inserted in the string) then it works on both MySQL and Oracle, see answer of "onedaywhen". some_col = '' doesn't work on Oracle as empty strings mean NULL there.
– Johanna
May 18 '15 at 14:07
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data.table vs dplyr: can one do something well the other can't or does poorly?
...able , not so much with dplyr . I've read through some dplyr vignettes and examples that have popped up on SO, and so far my conclusions are that:
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SQL Server: Filter output of sp_who2
...MAX),
BlkBy VARCHAR(MAX),
DBName VARCHAR(MAX),
Command VARCHAR(MAX),
CPUTime INT,
DiskIO INT,
LastBatch VARCHAR(MAX),
ProgramName VARCHAR(MAX),
SPID_1 INT,
REQUESTID INT
)
INSERT INTO @Table EXEC sp_who2
SELECT *
FROM @Tab...
Download a single folder or directory from a GitHub repo
...s://github.com/lodash/lodash/trunk/test
Download the folder. Go to the command line and grab the folder with SVN.
svn checkout https://github.com/lodash/lodash/trunk/test
You might not see any activity immediately because Github takes up to 30 seconds to convert larger repositories, so be patie...
How do I match any character across multiple lines in a regular expression?
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and what if i wanted just a new line and not all characters ?
– Grace
Apr 11 '11 at 12:02
3
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Clang vs GCC - which produces faster binaries? [closed]
I'm currently using GCC, but I discovered Clang recently and I'm pondering switching. There is one deciding factor though - quality (speed, memory footprint, reliability) of binaries it produces - if gcc -O3 can produce a binary that runs 1% faster, or Clang binaries take up more memory or just fai...
MySQL stored procedure vs function, which would I use when?
I'm looking at MySQL stored procedures and function. What is the real difference?
5 Answers
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What is the difference between an expression and a statement in Python?
In Python, what is the difference between expressions and statements?
14 Answers
14
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What is the JavaScript convention for no operation?
...at is the JavaScript convention for no operation? Like a Python pass command.
6 Answers
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Return type of '?:' (ternary conditional operator)
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Expressions don't have return types, they have a type and - as it's known in the latest C++ standard - a value category.
A conditional expression can be an lvalue or an rvalue. This is its value category. (This is somewhat of a simplification, in C++11 we have lvalues, xvalues a...