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T-SQL: Deleting all duplicate rows but keeping one [duplicate]
...is:
WITH cte AS (
SELECT[foo], [bar],
row_number() OVER(PARTITION BY foo, bar ORDER BY baz) AS [rn]
FROM TABLE
)
DELETE cte WHERE [rn] > 1
Play around with it and see what you get.
(Edit: In an attempt to be helpful, someone edited the ORDER BY clause within the CTE. To be clear, yo...
C# Interfaces. Implicit implementation versus Explicit implementation
...mentation allows you to access the interface through the class you created by casting the interface as that class and as the interface itself. Explicit implementation allows you to access the interface only by casting it as the interface itself.
MyClass myClass = new MyClass(); // Declared as concr...
How to get size of mysql database?
...) / 1024 / 1024, 1) "DB Size in MB"
FROM information_schema.tables
GROUP BY table_schema;
This query comes from the mysql forums, where there are more comprehensive instructions available.
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Can't start site in IIS (use by another process)
... you need to go on the Details tab to search for the PID. Or, as mentioned by @Nikita G in the comments, you can use this command to find the task from your command prompt:
tasklist /FI "PID eq 123"
Note: change 123 with the PID returned from the first command.
...
What are queues in jQuery?
... They are First-In-First-Out (FIFO). You can add a function to the queue by calling .queue(), and you remove (by calling) the functions using .dequeue().
To understand the internal jQuery queue functions, reading the source and looking at examples helps me out tremendously. One of the best examp...
MySQL load NULL values from CSV data
...at can contain from 3 to 4 columns of numerical values which are separated by comma. Empty fields are defined with the exception when they are at the end of the row:
...
What is the “volatile” keyword used for?
...ptimization and caching, and thus is useful when a variable can be changed by another thread.
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How to delete from select in MySQL?
...posts WHERE id IN (
SELECT * FROM (
SELECT id FROM posts GROUP BY id HAVING ( COUNT(id) > 1 )
) AS p
)
Or use joins as suggested by Mchl.
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Finding ALL duplicate rows, including “elements with smaller subscripts”
...ovide a reproducible example, so here's an illustration kindly contributed by @jbaums
vec <- c("a", "b", "c","c","c")
vec[duplicated(vec) | duplicated(vec, fromLast=TRUE)]
## [1] "c" "c" "c"
Edit: And an example for the case of a data frame:
df <- data.frame(rbind(c("a","a"),c("b","b"),...
Android destroying activities, killing processes
...he next activity will not be resumed until this method
returns. Followed by either onResume() if the activity returns back to
the front, or onStop() if it becomes invisible to the user.
onStop() Called when the activity is no longer visible to the user, because another activity has been res...