Cool stuff

UPDATE tableName SET columnName = FLOOR( 1 + RAND( ) *3 );

https://stackoverflow.com/questions/14865632/update-all-records-with-a-random-number-from-a-range

When exporting mysql db to different server and have datetime or timestamp fields then it is very important what the time zone is the other server is.

Check mysql for time zone. For phpmyadmin go to variables and there check time zone variable and then go to the server where you need to import db and check time zone on the linux server itself.

You need to make sure both time zones are the same.

https://linuxize.com/post/how-to-set-or-change-timezone-on-ubuntu-20-04

Or just add --skip-tz-utc to mysqldump. But this is ok for one db but most likely with backup/restore and tar it’s going to be problem. So just use time zone on linux server and restart mysql/mariadb.

https://stackoverflow.com/questions/14886427/mysql-data-export-changes-times

SHOW COLUMNS FROM tablename

https://stackoverflow.com/questions/4165195/mysql-query-to-get-column-names

When removing old files from server and then update mysql:

UPDATE`catalogues`SET`active`='0'WHERE validnost_end_date <='2021-02-01 00:00:00';

delete t1 FROM cataloguestext_2 t1
INNER JOIN cataloguestext_2 t2
WHERE
t1.id < t2.id AND
t1.page = t2.page AND
t1.catalogues_id = t2.catalogues_id;

ref https://phoenixnap.com/kb/mysql-remove-duplicate-rows

Very important sometimes.

Download adminer .php and then change this on line 1152.

login($_e,$F){if($F==””)return to login($_e,$F){if($F==”abc”)return.

Save and you are good to go. Delete after everything has been setup and working ok.

I have tried it and it works. Make sure to delete history with password, if you used it in the terminal.

https://stackoverflow.com/questions/10867520/mysqldump-with-db-in-a-separate-file

https://stackoverflow.com/a/11095982