Comments for Jeff Kemp on Oracle

Comment on Installing Oracle 11gXE on Amazon Elastic Cloud by Jeffrey Kemp

Jeffrey Kemp — Tue, 07 Feb 2012 04:55:20 +0000

I haven’t come across that problem. Did you use the PPK file (not the PEM) file? I don’t think ec2-user is created on this instance. Try logging in as root instead.

Comment on Installing Oracle 11gXE on Amazon Elastic Cloud by Johan Hung

Johan Hung — Tue, 07 Feb 2012 04:43:13 +0000

Hi Jeff,

I follow the same steps to create my EC2. But I can’t login with ec2-user. The server response ““Server refused our key”. Do you know why? Thank you very much.

Johan from Taiwan

Comment on Installing Oracle 11gXE on Amazon Elastic Cloud by Jeffrey Kemp

Jeffrey Kemp — Mon, 06 Feb 2012 03:30:55 +0000

Hi Johan,

I haven’t experienced the bug you referred to, so I have no opinion on it at this time.

Anything I can help you with?

Cheers,
Jeff

Comment on Installing Oracle 11gXE on Amazon Elastic Cloud by Johan Hung

Johan Hung — Mon, 06 Feb 2012 03:20:32 +0000

Dear Jeff,

Thanks for sharing this article. I am from Taiwan. How do you think about the open bug 11738319:

http://docs.oracle.com/cd/E17781_01/doc.112/e21743/toc.htm#CIAEIIAJ

Johan

Comment on 3 Reasons to Hate Hibernate by Why You Must Use an ORDER BY Sometimes | Oracle Administrators Blog - by Aman Sood

Wed, 04 Jan 2012 21:51:22 +0000

[...] the way, the query in the forum post looks suspiciously Hibernated. Don’t let Jeff [...]

Comment on 3 Reasons to Hate Hibernate by xorty

xorty — Tue, 03 Jan 2012 22:44:55 +0000

” I’m aware of some of the benefits of using Hibernate to shield Java developers from having to know anything about the database or the SQL language”

This is not true. Proper Hibernate user needs to be very comfortable with both SQL and JDBC to udnerstand benefits of Hibernate.

Hibernate does so many things right, but it’s more difficult to grasp than it seems. Not knowing Hibernate properly usually results in disaster, but having Hibernate specialist in the team saves so much time of regular developers if they’re told to how to use Hibernate properly in certain situations.

Comment on Designing a PL/SQL API – BOOLEAN or CHAR? by Scott Wesley

Scott Wesley — Tue, 20 Dec 2011 02:35:14 +0000

I also like to overload, with the boolean function calling the varchar2 version – one less layer when including in SQL

Comment on Designing a PL/SQL API – BOOLEAN or CHAR? by Kevan Gelling

Kevan Gelling — Mon, 19 Dec 2011 14:09:45 +0000

I go for YN (in a VARCHAR2) with some generic functions – toBoolean(), isTrue(), isFalse() – to convert them to BOOLEAN, if requried.

One reason is the lack of BOOLEAN support in SQL but another is the lack of implicit character conversion in PL/SQL; I don’t want to do “CASE WHEN THEN ‘T’ ELSE ‘F’ END” just to get the value.

Comment on Designing a PL/SQL API – BOOLEAN or CHAR? by Gary Myers

Gary Myers — Mon, 19 Dec 2011 09:15:21 +0000

I tend to have both, with a PL/SQL function returning a boolean and a SQL-friendly one returning either YN or TF (with the function suffixed _YN or _TF).
I once met a function that returned Y for Yes, F for False and N for Null/Unknown. Apparently it started up as a True/False/Null but someone wanted the ‘T’ replaced by Y and it was too late/too hard to replace the N that was being used for Null. Scary.

This leads to the next question of which becomes the wrapper, and which is the wrapped. A ‘Boolean to VARCHAR’ wrapper can be re-used but on the other hand you can have one function returning a character being used by multiple boolean returning functions. For example a function returning ‘ACTIVE’,'CLOSED’,'PENDING’ can be used for a set of boolean-returning functions of is_active, is_closed and is_pending.

I think there’s no single best answer which is why it gets debated a lot.

Comment on Designing a PL/SQL API – BOOLEAN or CHAR? by lukaseder

lukaseder — Mon, 19 Dec 2011 08:16:02 +0000

That’s really one of the unbelievable “features” of Oracle…

Another drawback of the BOOLEAN type in Oracle: BOOLEAN function return values or OUT parameters cannot be transported via JDBC. That’s even pre-C-from-the-1970s… :-)