有哪位大神清楚Oracle的RowCR(行一致读)机制，求科普！

wolfop

Yong Huang 发表于 2015-9-18 03:59
wolfop,

In response to your message #6. What you describe is what Oracle should do. But apparentl ...

看来是我的知识没尽快更新了，毕竟MVCC开销太大，改用2VCC开销小很多。

Yong Huang

wolfop 发表于 2015-9-18 00:55
看来是我的知识没尽快更新了，毕竟MVCC开销太大，改用2VCC开销小很多。

That's still an interesting comment. Could you elaborate, especially related to Oracle's RowCR feature? Thanks.

wolfop

Yong Huang 发表于 2015-9-19 00:25
That's still an interesting comment. Could you elaborate, especially related to Oracle's RowCR fea ...

This is quite simple, 2VCC just need provide commit data to client no need maintain the read consistant and choose which SCN data. Therefore 2VCC will be much easier to implementation and low cost. That is why timesten/IDS/DB2 choose it.