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DB2 commands

Starting the database [db2inst1@bloemkool ~]$ db2start 01/11/2022 14:57:48 0 0 SQL1063N DB2START processing was successful. SQL1063N DB2START processing was successful. [db2inst1@bloemkool ~]$ Stopping the database [db2inst1@bloemkool ~]$ db2stop 01/11/2022 14:58:43 0 0 SQL1064N DB2STOP processing was successful. SQL1064N DB2STOP processing was successful. [db2inst1@bloemkool ~]$ Stopping the database when there are connections/applications in the database.At first […]

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Basic Rman Configuration

A basic rman configuration (backups to disk): RMAN> show all; RMAN configuration parameters for database with db_unique_name TINUS are: CONFIGURE RETENTION POLICY TO RECOVERY WINDOW OF 31 DAYS; CONFIGURE BACKUP OPTIMIZATION ON; CONFIGURE DEFAULT DEVICE TYPE TO DISK; CONFIGURE CONTROLFILE AUTOBACKUP ON; CONFIGURE CONTROLFILE AUTOBACKUP FORMAT FOR DEVICE TYPE DISK TO ‘/u04/backups/tinus/%F’; CONFIGURE DEVICE TYPE […]

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$SQLPATH vs $ORACLE_PATH

Every time I install a new oracle machine it hits me: Why is login.sql not executed when I start a sqlplus session. So here is a quick reminder for myself: sqlplus is not looking in $SQLPATH for login.sql ….. it is looking in $ORACLE_PATH   So set $ORACLE_PATH and you will be fine.   This […]

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Bifurcation

Let’s say I have the formula Y(n+1)= λ*Y(n)(1-Y(n)) So the value of Y at time n+1 is some factor (λ) times Y at time n times 1 minus Y at time n. Y is between 0 and 1.  λ can be anything. As a starting point I choose Y0 to be 0.5 and λ=1. (In […]

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Sierpinsky

Sierpinsky Triangle A Sierpinsky trianlge looks like: The above example is not to much developed….but you will get the idea. A Siepinsky triangle can be constructed the following way: Draw a triangle and color it completely black In every black triganle you see in the image do the following Create a white triangle by choosing […]

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Recursive SQL in DB2

Problem Playing around in DB2 I wanted to know how to create a hiearchical query. This because I wanted to create view for explain plans, a bit resembling the explain plans which oracle provides. First step is understanding how to make the recursive SQL’s The setup: drop table relations; create table relations (id int, parent […]

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Create bridge device on my KVM host

I installed KVM on my debian host. Since I have 8 cores and 32GB RAM I have room to play around 🙂 And since I have some experience with KVM it was the obvious choice. Installing KVM : easy … apt is your friend Creating an VM : easy … Maybe I’ll once write it […]

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vi beep

I’m was going crazy because off the annoying bell sound vi(m) makes all the time. To solve it I put “set belloff=all” in my .vimrc martijn@radijs:~$ cat .vimrc set belloff=all martijn@radijs:~$

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DIG

Whenever I need to do something concerning DNS resolving I resort to dig. Some examples: Getting the IP adres for maboc.nl: martijnmbos@penguin:~$ dig maboc.nl ; DiG 9.11.5-P4-5.1+deb10u3-Debian maboc.nl ;; global options: +cmd ;; Got answer: ;; ->>HEADERHEADERHEADERHEADER

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Debian apt commands

I just installed a Debian machine. And since I’m a very longtime RedHat/Fedora man now I’m struggling with the commands to install stuff. Here are my notes: apt update Updates the meta-data and repositories apt upgrade Actually upgrades packages who need upgrading apt install <package> Installs a package apt list [package] Displays all packages known […]

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