What is the default isolation level of the SQL-Toolkit plugin?

When a database connection is created by Geneos (whether through Database Logging or SQL-Toolkit), the initial isolation level is indeed set to REPEATABLE_READ - this is explicit and hard coded. You can, however, change the isolation level for a specific query.

For Sybase, for example, you can change the isolation level in the query with at isolation clause.

You can use the following two statements query the same table at isolation levels 0 and 3, respectively. (We have taken below example from this Sybase documentation)

select *
from titles
at isolation read uncommitted

select *
from titles
at isolation serializable