public static TransactionIsolationLevel valueOf(int val) {
        switch (val) {
            case Connection.TRANSACTION_READ_UNCOMMITTED: return READ_UNCOMMITTED;
            case Connection.TRANSACTION_READ_COMMITTED: return READ_COMMITTED;
            case Connection.TRANSACTION_NONE: return NONE;
            case Connection.TRANSACTION_REPEATABLE_READ: return REPEATABLE_READ;
            case Connection.TRANSACTION_SERIALIZABLE: return SERIALIZABLE;
            default: return UNKNOWN;
        }
    }
The transaction isolation level wasn't specified or is unknown to jdbi.
core/src/main/java/org/jdbi/v3/core/transaction/TransactionIsolationLevel.java