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Oracle Isolation Levels : Read committed (315)

原创 Oracle 作者:tsinglee 时间:2007-12-06 12:12:08 0 删除 编辑

This is the default transaction isolation level. Each query executed
by a transaction sees only data that was committed before the
query (not the transaction) began. An Oracle query never reads
dirty (uncommitted) data.
Because Oracle does not prevent other transactions from
modifying the data read by a query, that data can be changed by
other transactions between two executions of the query. Thus, a
transaction that runs a given query twice can experience both nonrepeatable read and
phantoms.

Oracle隔离级别 : 已提交读取
1. Oracle默认的事务隔离级别
2. 事务内执行的查询只能看到查询执行前就已经提交的数据. Oracle 的查询永远不会读取脏数据

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