I will explain the solution when the processing is clogged with the following console output when executing flask db upgrade
using Flask-Migrate.
In this situation, you cannot exit the process with Ctrl + C, and even if you close the terminal, the changes in the DB schema will not be reflected.
$ flask db upgrade
INFO [alembic.runtime.migration] Context impl PostgresqlImpl.
INFO [alembic.runtime.migration] Will assume transactional DDL.
INFO [alembic.runtime.migration] Running upgrade 576e5f4a0fe7 -> 2b28fe44cc94, empty message
The cause is probably a clogged process that kills the offending process. It's almost the same, but I'll show you how to solve 4 patterns. Since 2 to 4 have not been verified, it may not be possible to solve it.
Kill the process on the terminal.
When you execute the ps
command, a list of running processes is displayed. You can find the corresponding process in it and kill it with the kill
command.
##Examine the process that postgres is running
ps aux | grep postgres
##End the relevant process
kill <<Process ID>> # ex) kill 12345
Do it on postgres. You may not be able to terminate the process this way.
##Examine the locked process
SELECT * FROM pg_locks; #The number in the pid column is the process ID
##End the process
SELECT pg_cancel_backend(Process ID);