|
|
1。SQL*PLUS GUI没有了，以iSQL*PLUS取代
It may surprise a lot of DBAs to learn that support for the Windows SQL*Plus GUI will be lost in Oracle 10i (although the product will probably still ship). The browser-based iSQL*Plus will replace it.
2。SQL*PLUS中的COPY命令将被抛弃
Within SQL*Plus the COPY command, much loved by experienced DBAs for quickly shifting large amounts of table data between databases, will be deprecated.
3。原有的Oracle Naming Tech将被directory naming取代（这个在9i里面就已经开始倡导了）
Oracle Names will be another casualty of 10i. Oracle's legacy service naming technology will be replaced by directory naming with LDAP-compliant directory servers.
4。RBO将不再被支持，全部由CBO替代（表示怀疑）
Support for the Rule-Based Optimizer (RBO) will also disappear in Oracle 10i, finally forcing DBAs to switch to the Cost-Based Optimizer (CBO).
5。RAC支持将被加强
Oracle 10i is expected to include Oracle Real Application Cluster (RAC) support for Sun, HP and IBM Unix boxes, bringing them up to date with technology currently available for Windows and Linux.
下面是一些对Oracle10i将取消对RBO的支持的言论，懒得翻译了，相信大家看得懂
One Oracle guru said that the beta is already out and that it contains changes that well might entail grueling migration work on the part of database administrators. Donald Burleson, CEO of Burleson Oracle Consulting and author of the Oracle Press book on SQL tuning, "Oracle High Performance SQL Tuning," pointed to a note sent out earlier this year to subscribers of Oracle Support Services' OracleMetaLink, an online support feature for Oracle customers. The note outlined planned de-support of the RBO (rule-based optimizer) in 10i.
The RBO, a key database component that determines the best way to execute complex SQL statements, is in use in nearly 50 percent of production systems, Burleson said.
Many enterprises are slowly migrating off RBO and onto CBO (cost-based optimization). Oracle's MetaLink note states that over 80 percent of customers are using CBO with Oracle8i and that the number is likely higher with Oracle9i. Oracle10i will only support CBO.
The note does not specify whether or not 10i will continue to support Rule hints, which would enable customers to defer SQL changes and continue to use RBO. If Oracle10i does drop system-wide RBO and Rule hints, customers are in for a load of work, Burleson said. "Companies will have to save their existing SQL execution plans with the Oracle 'Optimizer plan stability' feature," said Burleson, in Raleigh, N.C. "For companies with tens of thousands of SQL statements, this could be a major undertaking. … It's exciting, but not in a good way—in an 'Oh my God, I have to change my Optimizer' kind of way."
But Kelly Cox, an Oracle DBA who runs a small consultancy in Alexandria, Va., said that letting go of the RBO is fine with her. Beginning with version 8i, Oracle had made it clear that it would go in the direction of CBO support, she said, and she has been getting clients to migrate in that direction.
"The CBO, starting in [Oracle] 7.3, was reliable," Cox said. "With 7.0, there were a lot of problems, and there was significant distrust because of the problems it had. … [But I've been] happy with the results of CBO. One client, just turning on the CBO and running statistics, he had queries that took 45 minutes to run under RBO that are now taking 10 minutes [under CBO]."
Indeed, because de-support comes as no surprise, many users are taking it in stride. Carl Dudley, whose title is Oracle Associate Dean at Staffordshire University, in England, has been director of the U.K. Oracle User Group since 1988 and director of the European Oracle Group since 1994. Dudley is an Oracle10i beta tester who's received beta documentation and is now awaiting the code.
"The RBO has been threatened for many years," he wrote in an e-mail exchange. "It will still be an issue for a large proportion of the user population, but there are workarounds in many cases. I don't think it will too bad for us as we have little in the way of packaged applications. Our applications are written (mainly) in-house so we should be able to cope (with careful planning)."
Dudley said he isn't alarmed at the idea of RBO de-support because, for one, there are workarounds such as Rule hints. Also, he expects Oracle will likely offer extended support for RBO—for a price.
|
|
