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How to track down log4net problems
...
Make sure the root application where your entry point is logs something to log4net. Give it one of these:
private static ILog logger = LogManager.GetLogger(typeof(Program));
static void Main(string[] args)
{
logger.InfoFormat("{0} v.{...
Python Pandas merge only certain columns
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You can use .loc to select the specific columns with all rows and then pull that. An example is below:
pandas.merge(dataframe1, dataframe2.iloc[:, [0:5]], how='left', on='key')
In this example, you are merging dataframe1 and dataframe2. You h...
How can I sort arrays and data in PHP?
... $array[$j] = $tem;
}
}
}
return $array;
}
Selection sort
From the Wikipedia article on Selection sort:
In computer science, selection sort is a sorting algorithm, specifically an in-place comparison sort. It has O(n2) time complexity, making it inefficient on la...
How to concatenate strings with padding in sqlite
...qlite-lpad-rpad-function/
-- the statement below is almost the same as
-- select lpad(mycolumn,'0',10) from mytable
select substr('0000000000' || mycolumn, -10, 10) from mytable
-- the statement below is almost the same as
-- select rpad(mycolumn,'0',10) from mytable
select substr(mycolumn || '0...
Imply bit with constant 1 or 0 in SQL Server
Is it possible to express 1 or 0 as a bit when used as a field value in a select statement?
8 Answers
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How to un-submodule a Git submodule?
...n
>&2 echo "Error: No git repository found. Must be run from the root of a git repository"
usage
exit 1
fi
declare path="$(git config -f .gitmodules --get "submodule.${sub}.path")"
declare url="$(git config -f .gitmodules --get "submodule.${sub}.url")"
if [ -z "${path}" ]; then
>...
Complex CSS selector for parent of active child [duplicate]
Is there a way to select a parent element based on the class of a child element in the class? The example that is relevant to me relating to HTML output by a nice menu plugin for http://drupal.org . The output renders like this:
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Returning IEnumerable vs. IQueryable
...mers = custs.Where(c => c.IsGold);
That code will execute SQL to only select gold customers. The following code, on the other hand, will execute the original query in the database, then filtering out the non-gold customers in the memory:
IEnumerable<Customer> custs = ...;
// Later on...
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Which SQL query is faster? Filter on Join criteria or Where clause?
...INNER JOIN with a LEFT JOIN.
In your very case this will look like this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x
ON x.TableAID = a.ID
AND a.ID = 1
LEFT JOIN
TableB b
ON x.TableBID = b.ID
or this:
SELECT *
FROM TableA a
LEFT JOIN
TableXRef x...
nginx missing sites-available directory
...ath in step 3). Be sure to give it the right permissions/ownership. Likely root or www-data.
Move or copy your separate config files (just like you have in /etc/nginx/sites-available) into the directory conf.d.
Reload or restart nginx.
Eat an ice cream cone.
Any .conf files that you put into the ...