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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
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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...
How do I set the time zone of MySQL?
...+00:00'
@@global.time_zone variable
To see what value they are set to:
SELECT @@global.time_zone;
To set a value for it use either one:
SET GLOBAL time_zone = '+8:00';
SET GLOBAL time_zone = 'Europe/Helsinki';
SET @@global.time_zone = '+00:00';
(Using named timezones like 'Europe/Helsinki' ...
Eclipse doesn't highlight references anymore
... If none of comments above worked, uncheck "Mark occurrences of the selected element in the current file" > Apply > OK. Go back to preferences, check "Mark occurrences of the selected element in the current file" > Apply > OK.
– realPK
Feb 4 ...
Split a collection into `n` parts with LINQ?
... group item by i++ % parts into part
select part.AsEnumerable();
return splits;
}
}
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Random record from MongoDB
...llection.
db.mycoll.aggregate([{ $sample: { size: 1 } }])
If you want to select the random document(s) from a filtered subset of the collection, prepend a $match stage to the pipeline:
// Get one random document matching {a: 10} from the mycoll collection.
db.mycoll.aggregate([
{ $match: { a:...
How to change collation of database, table, column?
...he OP asked:
How to change collation of database, table, column?
The selected answer just states it on table level.
Changing it database wide:
ALTER DATABASE <database_name> CHARACTER SET utf8mb4 COLLATE utf8mb4_unicode_ci;
Changing it per table:
ALTER TABLE <table_name> CON...
How to fix .pch file missing on build?
...the bottom of the drop-down menu.
At the top left of the Properties Pages,
select All Configurations from the drop-down menu.
Open the C/C++ tree and select Precompiled Headers
Precompiled Header: Select Use (/Yu)
Fill in the Precompiled Header File field. Standard is stdafx.h
Click Okay
If you do n...
PostgreSQL: Modify OWNER on all tables simultaneously in PostgreSQL
...and sequences too. Here's what I did:
Tables:
for tbl in `psql -qAt -c "select tablename from pg_tables where schemaname = 'public';" YOUR_DB` ; do psql -c "alter table \"$tbl\" owner to NEW_OWNER" YOUR_DB ; done
Sequences:
for tbl in `psql -qAt -c "select sequence_name from information_schem...
Install MySQL on Ubuntu without a password prompt
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sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password password your_password'
sudo debconf-set-selections <<< 'mysql-server mysql-server/root_password_again password your_password'
sudo apt-get -y install ...