Posts
Using COLUMN in SQL*Plus
Here’s something I learned about SQL*Plus today. If you want to create a variable in a script, you can use the COLUMN command. In the following script, 2 variables called HOST_NAME and DATABASE_NAME are created. Their values are filled in when the SELECT statement executes. col host_name new_value HOST_NAME col instance_name new_value DATABASE_NAME SELECT host_name, instance_name FROM v$instance; UPDATE table SET value = '&&HOST_NAME'
Using Oracle with Ruby on Rails
If you want to use the Ruby Oracle OCI driver with Ruby on Rails, you might run into problems with the configuration. In the database.yml file, the following should be used to specify the host : host: localhost/mydatabase The mydatabase part is the the name of your database. For the adapter ‘oci’ should be specified. The database, username and password fields should be filled in as usual. Thanks to Duane’s Brain for pointing that out.
Paginating the results from a query in Oracle
MySql has some interesting additions to standard SQL to show paginated results : the LIMIT n OFFSET skip clause. The website http://troels.arvin.dk/db/rdbms/#select-limit-offset shows a way of doing this in Oracle.
Little Ruby script for generating passwords
Ruby is a scripting language, in the same league as Perl and Python. It is fully object-oriented, and comes batteries includes like Python, which means it comes with a full library installed by default. It is receiving a lot of attention these days due to the Ruby on Rails web application framework, which is indeed a very capable and surprisingly easy to use framework (probably more on this in a later article).