sar usage
I like to use the linux utility sar (system activity reporter (?)) I gives a fast and quite complete overview […]
Oracle, Script
ORAENV_ASK
Just a reminder I keep forgetting what the environment variable is called: ORA_ASKENV ORA_ENVASK ORAASK_ENV ORAENV_ASK This is _the_ variable: […]
linux, Uncategorized
tcpdump
Just a write up of the filters I sometimes use/need. (work in progress…) Filtering _out_ ssh: tcpdump “port ! ssh” […]
ansible, linux
ansible reboot after updating packages
When installing security/kernel packages the system must be rebooted. It would be a bit silly to reboot always. So..without further […]
Cost, DB2, Explain, SQL
DB2 : Cost Calculation 3 : index only revisited
Index Why In the DB2 : Cost Calculation 2 : index only post I noticed something upsetting, well, at least […]
Cost, DB2, Explain, Index
DB2 Cost : index of articles
I started a series of articles concerning the cost of queries (and as a consequence concerning the choices the optimizer […]
Cost, DB2, Index
DB2 : Cost Calculation 2 : index only
Index Why indexes Searching through millions of rows can be the right thing to do (TBSCAN). It might be the […]
Cost, DB2
DB 2 : Cost calculations 1 : Table Scan
Index Why? When you supply DB2 with a query DB2 has to make some serious decisions: – Should indexes be […]
DB2, Explain
DB2 Explain plan doesn’t exists
Just a quick reminder: If you start a new database where you want to genrate some execution-plans you might run […]
DB2, SQL
DB2 Row generator
Sometimes you need a mechanism to generate rows. For example when you need to create a demonstration table . Recursive […]