SET TRANSACTION statement only has effect until next COMMIT [CORE6111]

[firebird-automations]

Submitted by: @samofatov

This behavior is happening all the way to Firebird 1.0 builds.
I believe the engine shall preserve transaction isolation mode after commit;
Please correct me if I am wrong.

ISQL commands to reproduce:

SQL>create database '/tmp/test.fdb';
SQL>set transaction read committed;
SQL>select mon$isolation_mode from mon$transactions where mon$transaction_id=current_transaction;

MON$ISOLATION_MODE

             3 

SQL> commit;
SQL> select mon$isolation_mode from mon$transactions where mon$transaction_id=current_transaction;

MON$ISOLATION_MODE

             1 

[firebird-automations]

Commented by: @asfernandes

I disagree. SET TRANSACTION is kind of "start transaction" command and should not set "defaults" for next transactions.

[firebird-automations]

Commented by: @sim1984

I agree with Adriano. However, this does not eliminate the need to set parameters for a default transaction in ISQL. Maybe it makes sense to do some kind of ISQL command to set default transaction parameters for DML and DDL.