After reading how inadequate Doug was feeling over his IO subsystem, I decided to see how quick mine was…not that we’re getting into a “mine is better than yours” game, but rather to see how mine stacks up against Doug’s, bearing in mind his is a 5 disk stripe natively attached to his machine (I’m [...]
Archive of posts tagged dba
11g PX tracefiles now have the tracefile identifier on them
Now that I’ve got 11g up and running on OpenSuse 10.2 on a VMWare 6 VM, I’ve had time to do some playing with the latest and greatest release and the first thing I’ve noticed, when running some of Doug’s PX test scripts, is that the trace files generated for PX slaves now have the [...]
DBA_SEGMENTS misleading PARTITION_NAME column
Whilst writing some code that referenced the DBA_SEGMENTS dictionary view today, I realised that the contents of the PARTITION_NAME column actually contains the name of the subpartition when the table is a subpartitioned table…a script and results to illustrate: drop table jeff_unpartitioned purge/drop table jeff_partitioned purge/drop table jeff_subpartitioned purge/create table jeff_unpartitioned(col1 number,col2 number)/create table jeff_partitioned(col1 [...]
RDA gotcha with large number of files/tablespaces
I’ve talked before about the granularity of tables/partitions to tablespaces to datafiles being an important decision in building a data warehouse with pros and cons for each end of the spectrum – something I came across the other day was a small hindrance for the high granularity (i.e. lots of datafiles/tablespaces) approach. Mark Rittman had [...]