As promised, today my impressions of yesterday (confusing, I know). Clarification: This is about Wednesday, November 18th. I’m still at DOAG Conference 2009 in Nuremberg. Wednesday was a silent day for my interests, especially at noon there have been less talks being of interest, but maybe they have done something for my general knowledge… So […]
Tag: Oracle
DOAG Konferenz 2009: Impressions Day 1
These days, the DOAG Conference 2009 happens in Nuremberg, Germany. First day was yesterday, Tuesday November 11th 2009. This is a machine-readable copy of my scratchpad, coming from the different talks I attended. Sun Oracle Database Machine Exadata 2: The “Quarter Rack” (consisting of 2 Servers and 3 storage nodes) sounds interesting. 11gR2 has some […]
Oracle 11gR2 ASM / ACFS: A first benchmark (poorly)
Hi folks, since Oracle 11g Release 2 is out now, I had to test one of the most-missed ASM features: the ASM cluster file system ACFS. My Setup: Two VMware nodes with 2 CPUs and 1,5GB of RAM each Oracle Enterprise Linux 5.3 x86_64 Four virtual cluster disks from the ESX server, 10GB in size […]
Oracle 11gR2 ASM: Changed permission policy (ORA-15260)
Did you recently see the new error ‘ORA-15260: permission denied on ASM disk group’ in your ASM administration? Maybe you are still connected as SYSDBA, old habit from 10g? A quick citation from the Oracle Docs: The SYSOPER privilege permits the following subset of the ALTER DISKGROUP operations: diskgroup_availability, rebalance_diskgroup_clause, check_diskgroup_clause (without the REPAIR option). […]
Oracle: Executing an OS command from PL/SQL – ICMP ping from database
Executing OS commands from SQL or PL/SQL is easy as long as you are in SQL*PLUS – just do a host command. But I must confess, that this is a really useless hint. 🙂 Much more interesting is to execute an OS command with a DBMS_SCHEDULER job, but this is not possible in every case, […]
Oracle: Tracing of another session
I simply love 10046 level 12 traces. I described session tracing based on a logon trigger quite earlier, but some situations in real DBA life need this trace event switched on for a session other than my own AND for a short peroid in time (with no need for the connected user to log out). […]
Oracle Explain Plans or Execution Plans: Guess or Reality?
Oracle finally desupported the rule-based optimizer with version 10g. Since 9i, users are good adviced to make themself familiar with the cost-based-optimizer (CBO). In order to understand what happens with your statement after parsing with CBO involved, and to be able to tune your queries, displaying, understanding and optimizing explain- or execution plans is essential. […]
Get Oracle User DDL with dbms_metadata
Sometimes you have to recreate a user in a DB, and you like it to be the same as before again. To have its DDL at hand is usually rather convenient. DBMS_METADATA is a great toolbox to get it, my example is just a short but hopefully useful excerpt of its possibilities: set long 200000 […]
Oracle 11g JDBC driver hangs blocked by /dev/random – entropy pool empty
On a headless (=without console) network server, the 11g JDBC driver used for (java) application connect may cause trouble. In my case, it refused to connect to the DB without any error, trace or log entry. It simply hung. After several hours, it connected one time, and freezed again. Remote debugging done by the development […]
Creating Oracle AWR reports quicksheet
For comparing, classifying, benchmarking and forecasting databases, Oracle’s Automatic Workload Repository (AWR) is neat. (But remember! You will need a diagnostics pack license for that as described here and here – if you need a free technology for performance monitoring, consider using Craig Shallahamer’s OSM toolkit.) This post simply describes the package calls to create […]