SELECT
row_number() over (order by rowid) as snum,
a.*
from tbl_A a
--where rownum < 30

1 coarse-grained fine-grained
javaworld.com.tw 的这篇文章　讲得真是精辟

2 What is WSRP?
IBM's introduction.
I have been using it in WLW for a long time, but only know the theory behind the technology after this article.

3 J2CA
J2CA  ----  J2EE Connection Architecture

4 XA and non-XA
XA are for distributed transactions (as per the Open Group specificitions) and non-XA are not (transactions must be single-database).

Oracles is going to SMB.

Oracle Database XE is released as BETA version. it will be a biggest competitor to those free databases. e.g. MySQL, PostgreSQL. What it claims are all againt their current market
"

• Developers working on PHP, Java, .NET, and Open Source applications
• DBAs who need a free, starter database for training and deployment
• Independent Software Vendors (ISVs) and hardware vendors who want a starter database to distribute free of charge
• Educational institutions and students who need a free database for their curriculum

"

一个我一个多年在华新上问的问题。。。

today, i still see the usefulness. the answer to my question can be found in

http://www.jlcomp.demon.co.uk/faq/not_in.html

###############################################

[SQL] "NOT IN" VS "NOT EXISTS"

发贴时间：2003-08-25 17:38

any SQL expert can see the difference two the following two SQL

SQL 1
===============

SELECT t1.A1
FROM TBL1 t1
WHERE t1.A1 NOT IN
(
SELECT t2.A2
FROM TBL2 t2
)

SQL 2
=====================

SELECT t1.A1
FROM TBL1 t1
WHERE NOT EXISTS
(
SELECT t2.A2
FROM TBL2 t2
WHERE t1.A1 = t2.A2
)

in my application, SQL 2 does return some resutls.....
SQL 1 gives null.....

but they two looks similar...

Thanks!

http://www.webucator.com/resources/sql/reference.html