12c

MERGE JOIN CARTESIAN: a join method or a join type?

By Franck Pachot . I'll present about join methods at POUG and DOAG. I'll show how the different join methods work in order to better understand them. The idea is to show Nested Loops, Hash Join, Sort Merge Join, Merge(…)

Documentum – DA 7.3 showing java.lang.NullPointerException on every actions

Last year, we started to upgrade some Documentum Administrator from 7.2 to 7.3 and directly after, we started to see some NullPointerException on the log files. We are using DA 7.3 on some recent WebLogic Servers versions (12.1.3, 12.2.1.2). We(…)

WebLogic – Cannot register for disconnect events on local server

When working with WebLogic, there will probably be a moment when you will ask yourself: damn, what is wrong? Nowadays, software are so complex that it is kind of easy to introduce bugs/non-wanted behaviors in them… In this blog, I(…)

Trace files segmented in multiple parts as a workaround for bug 23300142

Today I visited a customer, who deleted a Data Guard configuration (i.e. a temporary Data Guard setup through the broker was deleted). The LOG_ARCHIVE_DEST_STATE_2 on the primary database was set to DEFER temporarily. That resulted in trace-files with name *tt*.trc(…)

CDB resource plan: shares and utilization_limit

By Franck Pachot . I'm preparing some slides about PDB security (lockdown) and isolation (resource) for DOAG and as usual I've more info to share than what can fit in 45 minutes. In order to avoid the frustration of(…)

Instance Caging and multitenant: do the right setting

When you want to do instance caging, you have to set manually CPU_COUNT and to set a resource manager plan. If you By Franck Pachot . only the CPU_COUNT no instance caging will occur. Except during the maintenance window where(…)

Adaptive Plan: How much can STATISTICS COLLECTOR buffer?

By Franck Pachot . The 12c adaptive plan prepares two join methods (Hash Join and Nested Loop), actives the one that has the better cost for the estimated cardinality and computes the point of inflection in cardinality estimation where the(…)

Fixed table automatic statistic gathering in 12c

By Franck Pachot . Before 12c, the fixed stats statistics were not gathered automatically. In 12c this has changed: even when you have never gathered fixed objects statistics you can see that you have statistics for X$ tables. That may(…)

12c multitenant: Cursor sharing in CDB

By Franck Pachot . In multitenant, there are two goals: consolidation within the same container database and isolation of pluggable databases. I see multitenant consolidation as an extension of schema consolidation. What is not possible in schema consolidation, such as(…)

OCM 12c preparation: Manage PDB

By Franck Pachot . Let’s see the different ways to create a PDB, with different tools. Same disclaimer here as in the first post of the series: don’t expect to get those posts close to what you(…)