+
Oracle adapters
for Ruby ORMs

Raimonds Simanovskis
TietoEnator Alise
@rsim github.com/rsim

What is
Ruby
on
Rails?

Ruby is
object-oriented
dynamic
programming language
simple from outside
powerful inside

Ruby on Rails
Web applications development framework
Developed in Ruby
Extracted from 37signals Basecamp application
Open source software
Focused on developer productivity
Agile software development approach

Main principles
DRY - Don’t Repeat Yourself
Convention over Configuration
Opinionated software

Components

Active Record (Model)

Action Controller

Action View

Ruby platforms
MRI 1.8.7
Ruby/YARV
JRuby
1.9.1
Rubinius IronRuby MacRuby
MagLev BlueRuby

Ruby => Oracle
require 'oci8'
Ruby application OCI8.new('scott', 'tiger').exec(
'select * from emp') do |r|
puts r.join(',')
end
ruby-oci8
Oracle [Instant]
Oracle Database
Client
SQL*Net

JRuby => Oracle
require "java"
sql =
Ruby application JavaSQL::DriverManager.getConnec
tion(db, user, password)
statement = sql.createStatement
status = statement.execute
"select * from parts;"
JRuby rs = statement.getResultSet()
JDBC driver Oracle Database
SQL*Net

ActiveRecord
Oracle Enhanced
Adapter

Ruby on Rails
=> Oracle
gem install activerecord-oracle_enhanced-adapter
database.yml
development:
adapter: oracle_enhanced
database: XE
username: blogdemo
password: blogdemo

SQL bind variables
Employee.find(1)
database.yml
ActiveRecord
development:
adapter: oracle_enhanced SELECT * FROM employees
database: XE WHERE (employees.id = 1)
username: blogdemo Oracle optimizer
password: blogdemo
cursor_sharing: force SELECT * FROM employees WHERE
(employees.id = :SYS_B_0)

Oracle Data Types
Ruby Rails Oracle
Fixnum :integer NUMBER
Float :float NUMBER
BigDecimal :decimal NUMBER, DECIMAL
Time :datetime DATE
Time :time DATE
Date :date DATE
String :string VARCHAR2
String :text CLOB
String :binary BLOB
True/FalseClass :boolean NUMBER(1), CHAR(1)

ActiveRecord
Extensions
set_date_columns
add_foreign_key
set_datetime_columns
set_boolean_columns
add_synonym
emulate_booleans
emulate_integers_by_column
add_primary_key_trigger
_name
set_create_method
ignore_table_columns
set_update_method
table_comment
set_delete_method
comment

Issues & Limitations
Identifiers up to 30
slow Data Dictionary views
characters
CLOB / BLOB usage in SQL
empty String == NULL
statements
Mac OS X is not well
absence of LIMIT, OFFSET
supported by Oracle :(

Multi-platform
support
oracle_enhanced adapter
Ruby/YARV
MRI 1.8.6/1.8.7 JRuby
1.9.1
ruby-oci8 1.x
ruby-oci8 2.x JDBC
or 2.x

DataMapper
• Alternative Ruby ORM
persistence framework
• Not just for relational databases

DataMapper Model

DataMapper differences
Conditions
Eager Loading
Identity Map
Lazy Loading

DataMapper & Oracle
DataMapper DataObjects adapter
DataMapper Oracle adapter
DataObjects Oracle driver DO JDBC Oracle driver
Ruby/YARV
MRI 1.8.6/1.8.7 JRuby
1.9.1
ruby-oci8 2.x ruby-oci8 2.x JDBC

DataMapper & Oracle
Type mapping Composite primary keys
Legacy schemas
Bind variables CLOB and BLOB values

PL/SQL calls from
Ruby
require "oci8"
conn = OCI8.new("hr","hr","xe")
cursor = conn.parse <<-EOS
BEGIN
:return := test_uppercase(:p_string);
END;
EOS
cursor.bind_param(':p_string',"xxx",String)
cursor.bind_param(':return',nil,String,4000)
cursor.exec
puts cursor[':return']
cursor.close

ruby-plsql gem
gem install ruby-plsql
require "ruby-plsql"
plsql.connection = OCI8.new("hr","hr","xe")
puts plsql.test_uppercase('xxx')

ruby-plsql gem
plsql.connection = OCI8.new("hr","hr","xe")
plsql.test_uppercase('xxx') # => "XXX"
plsql.test_uppercase(:p_string => 'xxx') # => "XXX"
plsql.test_copy("abc", nil, nil) # => { :p_to => "abc",
# :p_to_double => "abcabc" }
plsql.test_copy(:p_from => "abc", :p_to => nil, :p_to_double => nil)
# => { :p_to => "abc",
# :p_to_double => "abcabc" }
plsql.hr.test_uppercase('xxx') # => "XXX"
plsql.test_package.test_uppercase('xxx') # => 'XXX'
plsql.hr.test_package.test_uppercase('xxx') # => 'XXX'
plsql.logoff

class Employee < ActiveRecord::Base
set_create_method do
plsql.employees_pkg.create_employee(
:p_first_name => first_name,
:p_last_name => last_name,
PL/SQL CRUD :p_employee_id => nil
)[:p_employee_id]
procedures in end
set_update_method do
legacy plsql.employees_pkg.update_employee(
:p_employee_id => id,
applications :p_first_name => first_name,
:p_last_name => last_name
(with )
end
ActiveRecord) set_delete_method do
plsql.employees_pkg.delete_employee(
:p_employee_id => id
)
end
end

Thanks!
http://blog.rayapps.com
http://github.com/rsim
http://groups.google.com/group/
oracle-enhanced