Learning is not a spectator sport
Connor McDonald on SQL and the Oracle Database
Tag: triggers
More triggers are better
Yes, you heard me correctly. If you have got one trigger on a table, then you might be surprised to find that perhaps having a second one will be a better option. Then again, I also love the sweet scent of a clickbaity, inflammatory…
When WHEN went faster
Yeah…try saying that blog post title 10 times in a row as fast as you can But since we’re talking about doing things fast, this is just a quick post about a conversation I had a twitter yesterday about the WHEN clause in a…
Those pesky LONG columns
There was a time, many moons ago when CLOB, BLOB and BFILE did not exist as data types. So if you had anything longer than a few kilobytes of data to store, you had to use a LONG or a LONG RAW. But those…
Identity columns in 12c … just a sequence ?
This question came to me over Twitter, so I thought I’d whip out a quick post on it Yes, we do implement the IDENTITY column via a sequence. (Digression – I think this is a smart thing to do. After all, we’ve had…
DDL triggers – interesting results
This question came in on AskTom, yielding a very interesting result when it comes to DDL triggers. To set the scene, I’ll first create a table called T which is just a copy of SCOTT.EMP SQL> create table scott.t as select * from scott.emp;…
FOLLOWS clause
In early Oracle releases, you could have 1 trigger per type of trigger per table (eg if you had a before-row-insert trigger, you could have only 1). Now there is no limit. But that does raise the question – if I have “n” BEFORE…
Where did my triggers go ?
You need to be careful when coding and using triggers when it comes to Datapump (or anything that transposes triggers between schemas). A lot of people make assumptions about what will happen with their triggers, and often get a nasty shock when they see…
Avoiding public embarrassment with triggers
If you create a trigger that does not compile, any part of your application that refers to the table with the invalid trigger is basically dead until that trigger becomes valid. Even if a DML on that table is not going affect any rows,…
Dumb triggers part 2 – session level control
In the previous post, I pontificated about triggers that “lock you in” to having them fire, which can create dramas when it comes to doing data patching. Maybe you can design your application around this, but if you cant, the last thing you want…
Really dumb triggers
Some people hate triggers, some people love triggers… I am not that opinionated on them in either direction, but one thing I do hate, whether it be a trigger or not, is dumb code. And today’s post just happens to be about dumb code…
