transactions - How to obtain current isolation level on DB2? -

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i trying learn how transactions work in db , wrote following test sql:

savepoint stop_here on rollback retain cursors;  insert testschema."test" (id, name) values (89898, 'sdfasdfasd');  rollback savepoint stop_here;  select * testschema."test";

after execution of code 1 row added table. if add following line @ beginning:

set transaction isolation level read committed;

all work expected, i.e. transaction correctly rolled , no new entries in db, if run code again data studio shows me error in first line:

[sql0428] sql statement can not launched.

so questions are: there way obtain current isolation level , why can't set isolation level more 1 time?

i thankful answers , links.

ps. using db2/iseries v5r4.

pps. sorry bad english

you can current isolation level special register current isolation. sql0428 because didn't commit or rollback before setting isolation level, , there transactions still in process in session.


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