Re: New to Oracle
From: Daniel Morgan <damorgan_at_x.washington.edu>
Date: Sat, 25 Oct 2003 09:01:02 -0700
Message-ID: <1067097678.671116_at_yasure>
Oracle uses a multiversion concurrency model such that READS never block WRITES
and WRITES never BLOCK reads. Add to that the fact that locks are an infinite
resource and that there is no such thing as lock escalation and you start to get an idea of
how the differences can become critical.
The other area of very large differences is the security model. Look up the following at
tahiti. (1) ROLE, (2) PROFILE, (3) DBMS_RLS, (4) EXCLUDED NODES,
(5) SYSTEM PRIVILEGES, (6) TABLE PRIVILEGES. That will get you started.
Date: Sat, 25 Oct 2003 09:01:02 -0700
Message-ID: <1067097678.671116_at_yasure>
The most important differences in architecture that you must learn related to the fat thatThanks very much, I actually would like to know: "the very significant differences between the underlying architectures of Oracle vs DB2". beside how indexes are organize, authority to create database, table, table indexes. I also looking into SYS tables (the same as looking into SYSIBM tables for DB2). I understand that data types is somwhat different between the two. The link that you point to me is more structure and easier to navigate than search thru the whole manual (more relational to me!). Thanks againOracle vs DB2:"Daniel Morgan" <damorgan_at_x.washington.edu> wrote in message news:1067002024.263103_at_yasure...johnlinh wrote:Hi: I am from DB2 camp. I have just started to learn Oracle by download and install Oracle 8.1.7 client, connect to an existing Oracle DB. I also downloaded Oracle manual and walking thru it. I have tested what I have learned PS/SQL SQL/PLUS. Is there any site/book that I can compare Oracle functions with DB2? I would like to start from application development, building tables, tuning indexes (by looking into system tables),.... Your suggestion would be appreciated.Can't think of anything specific to DB2 to Oracle though it may well exist. But I would strongly urge you to go to http://tahiti.oracle.com and look at the CONCEPTS books. Be sure you understand the very significant differences between the underlying architectures of Oracle vs DB2: They are completely different. On the other hand converting PREVVAL to CURRVAL will be just about everything you will need to learn about sequences. Welcome. -- Daniel Morgan http://www.outreach.washington.edu/ext/certificates/oad/oad_crs.asp http://www.outreach.washington.edu/ext/certificates/aoa/aoa_crs.asp damorgan_at_x.washington.edu (replace 'x' with a 'u' to reply)
Oracle uses a multiversion concurrency model such that READS never block WRITES
and WRITES never BLOCK reads. Add to that the fact that locks are an infinite
resource and that there is no such thing as lock escalation and you start to get an idea of
how the differences can become critical.
The other area of very large differences is the security model. Look up the following at
tahiti. (1) ROLE, (2) PROFILE, (3) DBMS_RLS, (4) EXCLUDED NODES,
(5) SYSTEM PRIVILEGES, (6) TABLE PRIVILEGES. That will get you started.
-- Daniel Morgan http://www.outreach.washington.edu/ext/certificates/oad/oad_crs.asp http://www.outreach.washington.edu/ext/certificates/aoa/aoa_crs.asp damorgan_at_x.washington.edu (replace 'x' with a 'u' to reply)Received on Sat Oct 25 2003 - 18:01:02 CEST