On my story about using the minus SQL operator to compare tables, Blake asked what other more efficient methods could be used for tracking changes between tables.
Here are a couple options you could consider to compare table contents instead of the ‘minus’ operator:
Oracle change tables are probably the best for tracking changes internal to the database. You can see an example of them here.
This is what most Oracle data warehouse ETL is built with.
Custom triggers on insert, update and delete can enable similar functionality to change tables (change tables actually work with internal triggers.) You can have the triggers insert your data into another table or just keep some metadata in a separate table to indicate which rows have changed.
Simply adding an activity date column to your tables, populated with a trigger may be enough to track changes and keep databases in sync. If you know, for example, that the database was cloned at midnight on the 1st of the month, then to see what has changed since then you just need to examine all rows with an activity date after that. The activity date can be useful for several other things as well making this a fairly desirable approach.
Blake has an intriguingly eclectic blog himself which is well worth a visit. Thanks for the question Blake!
oracle, database, dba, database development, database administration
The Boston Globe reports that a little more than a week ago Symantec Corp. made public a major loss of data from Monster.com. While the stolen information does not include social security numbers or other banking information there is real concern that email addresses from Monster.com will not only be sold to spammers, but will be used in phishing scams.
Read the full article and followup from the Boston Globe.
Monster.com has decided to notify users of this breach by mail. That’s snail mail. Now, I don’t know about you, but my mailing address on Monster.com is far from up to date, so I think it’s important that we spread the word online!
Thanks to Joe at JVT Advisors for sending this on to me.
job, job search, monster, monster.com, data security, security
Work has me traveling more than usual right now and I’ve been spending quite a bit of time on a airplane. The following are some things I’ve heard on recent flights that didn’t exactly fill me with confidence:
Overheard between two flight attendants while boarding: “Well, so much for an on-time departure.”
Over the intercom before takeoff: “We’re going to have to ask everyone to close the shades on your windows to help keep it from getting too hot. We’re going to be without air conditioning for a while.”
A mother in the seat in front of me talking to her young child: “Does your tummy feel better since you had that pizza?”
If you’ve heard something you didn’t like on an airplane please leave a comment.
funny, fun, airplane, airline, travel
It’s funny, you wouldn’t think a dress made of thousands of condoms would be a pretty thing, but the overall effect is quite stunning!
Art MoCo offers some explanation of why the artist Adriana Bertini creates these amazing dresses:
The Brazilian artist started creating fashions out of condoms to highlight the need to look at the prophylactics as basics, so that we would don them as easily as a pair of jeans. Some of her dresses use thousands of condoms; one wedding dress took almost 80,000 (and to think, some people hesitate over using just one!).
condom, sex, safe sex, birth control, prophylactic
The webcomic xkcd is so good I have to resist the urge to blog just about every strip, but the latest one is just too good not to share.
This of course applies not only to programmers, but sys-admins and DBAs as well. I mean really, some of those Oracle installs take a long time!
slacker, technology, compile, programming, code, excuse