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Get TransactionScope to work with async / await
...flow across thread continuations.
My understanding is that it is meant to allow you to write code like this:
// transaction scope
using (var scope = new TransactionScope(... ,
TransactionScopeAsyncFlowOption.Enabled))
{
// connection
using (var connection = new SqlConnection(_connectionStrin...
Get records with max value for each group of grouped SQL results
..., age desc, Person) x
group by `Group`
This works because in mysql you're allowed to not aggregate non-group-by columns, in which case mysql just returns the first row. The solution is to first order the data such that for each group the row you want is first, then group by the columns you want the...
How to do a scatter plot with empty circles in Python?
... colored disks already plotted by scatter() , so as to highlight them, ideally without having to redraw the colored circles.
...
php is null or empty?
...!
– Cagatay Ulubay
May 23 '17 at 12:32
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show 3 more comme...
Rearrange columns using cut
...
This is very often inefficient. Typically, you will find that the corresponding Awk script is a lot faster, for example. You should also be careful to quote the values "$col2" and "$col1" -- there could be shell metacharacters or other shenanigans in the data.
...
Portable way to get file size (in bytes) in shell?
...
One would guess the portable ls -ln FILE | { read _ _ _ _ size _ && echo "$size"; } needs not fork for the second step of the pipeline, as it uses just built-ins, but Bash 4.2.37 on Linux forks twice (still only one execve, though).
– Palec
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Passing additional variables from command line to make
... arguments? In other words, I want to pass some arguments which will eventually become variables in the Makefile.
8 Answers...
Difference between DateTime and Time in Ruby
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Newer versions of Ruby (2.0+) do not really have significant differences between the two classes. Some libraries will use one or the other for historical reasons, but new code does not necessarily need to be concerned. Picking one for consistency is probably best,...
Understanding implicit in Scala
..., which means the values will be taken from the context in which they are called. If there is no implicit value of the right type in scope, it will not compile. Since the implicit value must resolve to a single value and to avoid clashes, it's a good idea to make the type specific to its purpose, e....
Git pull results in extraneous “Merge branch” messages in commit log
...ine. A pull effectively runs git fetch and then git merge so a merge is usually happening when you run git pull.
The alternative to use rebasing instead of merging is possible, but usually you should avoid it. Rebasing allows you to keep a linear history, but also removes any information about the ...