database - 如何检查隔离级别？

Question

如何检查在我的 Oracle 数据库中设置了什么 IL。我该如何改变它？非常感谢。

Answer 1

设置隔离级别

For Read only Transaction isolation level

隔离级别可以设置为对于交易级别:

SET TRANSACTION ISOLATION LEVEL READONLY;

对于 session 级别:

ALTER SESSION SET ISOLATION_LEVEL READONLY;

For Serializable Transaction isolation level

交易级别:

SET TRANSACTION ISOLATION LEVEL SERIALIZABLE;

session 级别:

ALTER SESSION SET ISOLATION_LEVEL SERIALIZABLE;

For Read Committed Transaction isolation level

交易级别:

SET TRANSACTION ISOLATION LEVEL READ COMMITTED;

session 级别:

ALTER SESSION SET ISOLATION_LEVEL READ COMMITTED;  

找到隔离级别:

交易进行中:

SELECT s.sid, s.serial#,
   CASE BITAND(t.flag, POWER(2, 28))
      WHEN 0 THEN 'READ COMMITTED'
      ELSE 'SERIALIZABLE'
   END AS isolation_level
FROM v$transaction t 
JOIN v$session s ON t.addr = s.taddr AND s.sid = sys_context('USERENV', 'SID');

交易未进行时

declare 
   trans_id Varchar2(100);
begin
   trans_id := dbms_transaction.local_transaction_id( TRUE );
end;