Could not save product in Magento 2.1.9 after copying the database from another Magento 2.1.9 shop and changing the mysql user (f.e. if you copy your develop database to production server, the credentials do necessarily not match).
Error while saving a product: SQLSTATE[42000]: Syntax error or access violation: 1142 TRIGGER command denied to user olduser@host ...
Solution: Recreate the triggers in the new database.
Dump triggers: mysqldump -unewuser -p --triggers --add-drop-trigger --no-create-info --no-data --no-create-db --skip-opt newdatabase > triggers.sql
Open the triggers.sql file in an text editor and replace olduser with newuser or replace via shell: sed -i -e 's/olduser/newuser/g' triggers.sql
Afterwards delete the triggers via phpmyadmin or SQL (UNTESTED, from here: https://stackoverflow.com/a/30339930/5031113): SELECT Concat('DROP TRIGGER ', Trigger_Name, ';') FROM information_schema.TRIGGERS WHERE TRIGGER_SCHEMA = 'your_schema';
Then import the triggers via: mysql -unewuser -p newdatabase < triggers.sql
Everything should be fine now.
