April 2016 archive

EM SQL Monitor Impact

In case anyone needs a reminder, its always a good idea to determine the impact of your monitoring tools on the very database you are monitoring. Some monitoring tools are lightweight and others are more obtrusive. I am using Enterprise Manager 13c to monitor a specific SQL statement while its running. I noticed in another …

Continue reading

Recreate Bad RAC Node

Just recently, I was trying to apply the latest and greatest Patch Set Update (PSU) to a 2-node Oracle RAC system. Everything went smoothly on the first node. I did have problems when trying to apply the PSU to the second node. The problem wasn’t with OPatch or the PSU, but rather, I could not …

Continue reading

Oracle RAC N+1 Redundancy

I find that when people are designing Oracle RAC architecture, they often do not think of N+1 redundancy in their implementation plans. There are two reasons to implement Oracle RAC, availability and scalability. For the purposes of this discussion, I am focusing only on the availability side. If your RAC deployments are for scalability reasons …

Continue reading

V$SQL_SHARED_CURSOR TOP_LEVEL_RPI_CURSOR

I was working with an individual on a question in the MOSC forums recently where they asked about the TOP_LEVEL_RPI_CURSOR column of the V$SQL_SHARED_CURSOR view. There is little documentation on what this column is trying to tell the DBA. All the Oracle docs say is that this column contains “(Y|N) Is top level RPI cursor”. So …

Continue reading