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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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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...
Force drop mysql bypassing foreign key constraint
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If you are using phpmyadmin then this feature is already there.
Select the tables you want to drop
From the dropdown at the bottom of tables list, select drop
A new page will be opened having checkbox at the bottom saying
"Foreign key check", uncheck it.
Confirm the deletion by accepting ...
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...
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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When to use single quotes, double quotes, and backticks in MySQL
...ng query will produce different results (or errors) depending on SQL mode:
SELECT "column" FROM table WHERE foo = "bar"
ANSI_QUOTES disabled
The query will select the string literal "column" where column foo is equal to string "bar"
ANSI_QUOTES enabled
The query will select the column column where ...
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...
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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Finding median of list in Python
...t though: sorting is much more work in the worst case (Theta(n lg n)) than selecting the median (Theta(n))...
– Jeremy
Jun 11 '19 at 13:33
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Which data type for latitude and longitude?
...e using gist (geog);
and then request, say, 5 closest to a given point:
select *
from your_table
order by geog <-> 'SRID=4326;POINT(lon lat)'
limit 5;
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