The Worth of Certifications

NOTE: Howard has since taken his site offline while he finds a suitable webhost, so the first link probably won't workHoward Rogers recently touched on the knowledgeset (or lack thereof) of some interviewees with OCPs. We've all heard this before, and the common theme is that just because someone managed... [Read More]
Tags: oca ocp oracle

sqlplus commit-on-exit?

ACHTUNG: Did you know that SQL*Plus issues a COMMIT when you exit? This has nothing to do with the AUTOCOMMIT setting, which will automatically commit after every statement in sqlplus.If you issue a graceful exit (via the "exit" or "quit" command), sqlplus will always issue a commit. However, if you... [Read More]
Tags: sqlplus oracle

Temporary Tables and REDO Logs

Today in DBA class, the instructor matter-of-factly rattled off some characteristics on global temporary tables. Among these I just barely noticed him state that they generate REDO logging. I sat upright and asked him to confirm that I had heard him correctly, and indeed that is what he said. He... [Read More]

Track yer block changes

If you're using RMAN to take your backups, and are running Oracle 10g, do yourself a favor and enable block change tracking now. Prior to doing so, my level 1 incremental backups were scanning my entire database (~830 GB) and took over 5 hours. With BCT, level 1 incremental backups... [Read More]

selecting count(1) vs count(*)

Count me among the many who naively assumed that using count(1) instead of count(*) was somehow faster or less resource-intensive when counting the number records in a select query. Herod over at Yet Another Oracle DBA provides some more evidence on top of Tom Kyte's previous smackdown.
Tags: tuning oracle