Thursday, July 21, 2005

Changes to Daylight Savings!!

Are they nuts??? The change, if it goes ahead, will mean that it would be DST three months of the year. Why even bother? I would say the best thing is to abolish Daylight Saving Time. Think about the saving in time and effort in reprogramming all your microwave, vcr, etc.

On a non-related but Oracle-related note, I have been trying to trouble-shoot some performance issues with our migration of 8i to 9iR2. Since we had a spare server box, we decided to create a new 9i database and import the data from the 8i into the 9i database. Our developers tested the new database and found that performance overall was either the same or slightly faster than the 8i. One of the show stopper was the performance of the CREATE BITMAP INDEX for one of the big data table (approx. 180 million rows). It took 4 to 5 times longer on the 9i than on the 8i according to the developers. One of the problems is that the 9i database is not the same as the 8i database. For example, the 9i database was created with a default 32K block size compared to 8K for the 8i database. The table in question is partitioned in 9i but not the one in 8i. The CREATE BITMAP INDEX xxx ON yyy (zzz) took about 20 minutes in 8i but could be as long as 100 minutes in 9i.

So, now I am trying to collect stats for the various scenarios to see which could potentially give us either the same or better performance.

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