If we create a temporary table with the same name within a store procedure, and try to drop some columns in two different sessions running at the same moment, error " Unknown column" may pop.
Although this is documented in
"Temporary table names are specific to your session. They may conflict with other temporary tables from other sessions or shadow names of non-temporary tables."
But this is different behavior with Mysql
This means that two different sessions can use the same temporary table name without conflicting with each other or with an existing non-TEMPORARY table of the same name. (The existing table is hidden until the temporary table is dropped.)
This is stopper if using Mariadb as a drop in replacement for Mysql, as this require rewrite all SPs with alter temporary statement.