Category: nice to know

Currently, I work on a Teradata machine. I understand that Teradata is based on the idea that processes work in parallel with each other. The idea is that data are divided over so-called amps that each process their share of the data. If each so-called amp may process their share of data, the amount of…

There exist many ways to get data from Oracle. After all, this is the core functionality of Oracle: getting data in and out. A nice possibility is to retrieve data by means of a small script. Such script is straightforward: set echo off set pagesize 0 set feedback off set linesize 50 set termout off…

Oracle has introduced a small version of its DBMS that is labelled “XE”. This small version can be downloaded and used for free upon the condition that its usage is for personal study only. I really like this application: it has a relative small footprint; it runs on a small machine and it allows you…

In Oracle, it is quite well possible to display quickly how many non-nulls we have per column in a table. The script reads like: set termout off echo on feed off trimspool on head off pages 0 spool C:\countall.tmp SELECT ‘select count(‘||t.column_name||’) from ‘ || t.table_name ||’;’ FROM user_tab_columns t WHERE t.table_name = ‘DATE_D2’ ;…

Recently, I encountered a very nice script that allows us to get an overview of the number of records per table in an Oracle scheme. First the script: set termout off echo off feed off trimspool on head off pages 0 spool C:\countall.tmp select ‘SELECT count(*), ”’||table_name||”’ from ‘||table_name||’;’ from user_tables / spool off set…

Today, I heard someone complaining that he received a file that contained “unexpected characters”. Later it was discovered that this file was provided in EBCDIC and the receiver tried to open it on a UNIX box with an ordinary editor. Such a UNIX box assumes the ASCII lay-out and as the file was delivered in…

Yesterday, I encountered a small but convenient script that creates and loads a set of tables in an Oracle environment. It was part of an Informatica training, so I have to give the credits to those guys. Click here to get the Script I changed a few things in the script but not much. The…

Today I had to create a date dimension. This is a dimension that provides us with a list of records that contains the weekdays, the number of a month etc. Let me give a screenshot of these records: This table helps us to translate a date (like 08 – 25 – 2011) into a day…

I realise that working on a main frame can be very intimidating. Look at the JCL: the job language that you use to get things done. This is the way how you might copy files, how to execute a programme, to compile a programme. This implies that you will use the JCL every day when…

Recently, I was in a situation where I had to query a Db2 database on a mainframe. I was also in a situation where the knowledge and documentation on that mainframe was not very widespread. So there I found myself, sitting in the dark with only a so-called 3270 screen looking at me, waiting for…