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Heroku Postgres - terminate hung query (idle in transaction)
...'s not desirable or not an option ...)
Find the PID by running this sql:
SELECT pid , query, * from pg_stat_activity
WHERE state != 'idle' ORDER BY xact_start;
(The query may need mending dependent of the version of postgres - eventually, just select * from pg_stat_activity). You'll find the ...
Get size of all tables in database
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SELECT
t.NAME AS TableName,
s.Name AS SchemaName,
p.rows,
SUM(a.total_pages) * 8 AS TotalSpaceKB,
CAST(ROUND(((SUM(a.total_pages) * 8) / 1024.00), 2) AS NUMERIC(36, 2)) AS TotalSpaceMB,
SUM(a.used_pa...
How does Facebook Sharer select Images and other metadata when sharing my URL?
...s pulled from the source as a preview for their link. How are these images selected, and how can I ensure that any particular image on my page is always included in this list?
...
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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unable to copy/paste in mingw shell
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Right-click on the title bar of the command window and select 'Properties', then on the 'Options' tab tick the box for the 'QuickEdit mode', then click 'Ok'.
After that you can paste text from the clipboard using the right mouse-button, highlight text while holding down the left...
SQL Group By with an Order By
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In all versions of MySQL, simply alias the aggregate in the SELECT list, and order by the alias:
SELECT COUNT(id) AS theCount, `Tag` from `images-tags`
GROUP BY `Tag`
ORDER BY theCount DESC
LIMIT 20
share
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T-SQL datetime rounded to nearest minute and nearest hours with using functions
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declare @dt datetime
set @dt = '09-22-2007 15:07:38.850'
select dateadd(mi, datediff(mi, 0, @dt), 0)
select dateadd(hour, datediff(hour, 0, @dt), 0)
will return
2007-09-22 15:07:00.000
2007-09-22 15:00:00.000
The above just truncates the seconds and minutes, producing the resu...
Convert text into number in MySQL query
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This should work:
SELECT field,CONVERT(SUBSTRING_INDEX(field,'-',-1),UNSIGNED INTEGER) AS num
FROM table
ORDER BY num;
share
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improve this ...
How to build jars from IntelliJ properly?
...from IntelliJ:
Go to project structure:
Create a new artifact:
Select the main class, and be sure to change the manifest folder:
You have to change manifest directory:
<project folder>\src\main\java
replace "java" with "resources"
<project folder>\src\main\resources
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Difference between View and table in sql
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A table contains data, a view is just a SELECT statement which has been saved in the database (more or less, depending on your database).
The advantage of a view is that it can join data from several tables thus creating a new view of it. Say you have a database w...