I have a very long and complex legacy stored procedure which performs one single transaction. It has some concurrency issues though. Therefore, I decided that the procedure will be executed within a connection that has isolation level serializable, so that sequential execution will be simulated. The point is that there are some other applications accessing the same tables in the database (not using that procedure though) and their connection might not (and afaik has not) configured the isolation level to be serializable. The question now is: If the stored procedure is executed within a serializable isolation level connection, will that lead to all other connections (whatever isolation level they have configured) to not be able to read/alter the respective tables while the stored procedure within the serializable isolation level connection is executed?