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GROUP_CONCAT comma separator - MySQL
I have a query where I am using GROUP_CONCAT and a custom separator as my results may contain commas: '----'
3 Answers
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Avoiding memory leaks with Scalaz 7 zipWithIndex/group enumeratees
...e API, but I recently verified that an equivalent test passes against the scalaz-stream API. This is a newer stream processing API that is intended to replace iteratee.
For completeness, here's the test code:
// create a stream containing `n` arrays with `sz` Ints in each one
def streamArrs(sz: In...
How to find which rspec test is taking so long
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In RSpec 2 and 3, you can use the --profile flag or add --profile to your .rspec file. This will track the top 10 slowest examples.
For RSpec 1, you can use --format o with spec command. It shows a text-based progress bar with profiling of 10 slo...
Where do I mark a lambda expression async?
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Find an item in List by LINQ?
...efault to be my answer of choice - same as Single but returns 'null' if it can't find it.
– Eddie Parker
Mar 7 '13 at 5:46
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How do you rename a table in SQLite 3.0?
...is pretty thick. What is needed is a simple example of how that works. You can find that here: https://www.sqlitetutorial.net/sqlite-alter-table/
To be precise, in the most basic case it looks like this:
ALTER TABLE existing_table
RENAME TO new_table;
I am not sure if the dot notation works, bu...
MySQL how to join tables on two fields
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Basically, slowness is because concrete calculates new values that has no indexes so direct conditions should be faster. if even this query would be slow again, check is indexes exists, and sometimes creation one index for 2 fiel...
How to remove origin from git repository
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Is [CallerMemberName] slow compared to alternatives when implementing INotifyPropertyChanged?
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No, the use of [CallerMemberName] is not slower than the upper basic implementation.
This is because, according to this MSDN page,
Caller Info values are emitted as literals into the Intermediate
Language (IL) at compile time
We ca...
How to read the database table name of a Model instance?
Given a model's instance object, how can I get the database table's name?
1 Answer
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