So I can use this gem for active record: https://github.com/jruby/activerecord-jdbc-adapter
But, I want to use the following code on JRuby to connect to a legacy db and run some manual queries, how do I do using JRuby / Rails 4.0.0?
require 'pg'
conn = PGconn.connect("192.168.0.2", 5432, '', '', "mydb", "postgres", "password")
The docs suggest something along the lines of:
# connection setup
ActiveRecord::Base.establish_connection(
:adapter => 'jdbc',
:driver => 'org.postgresql.Driver',
:url => 'jdbc:postgresql:sample_db;create=true'
)
Or
ActiveRecord::Base.establish_connection(
adapter: 'postgresql',
database: 'db/my-database'
)
This is assuming you're using JDBC and the appropriate configuration. For this, I suggest taking a look at Postgres' documentation.
Sample provided over there is written in Java:
String url = "jdbc:postgresql://localhost/test";
Properties props = new Properties();
props.setProperty("user","fred");
props.setProperty("password","secret");
props.setProperty("ssl","true");
Connection conn = DriverManager.getConnection(url, props);
String url = "jdbc:postgresql://localhost/test?user=fred&password=secret&ssl=true";
Connection conn = DriverManager.getConnection(url);
...but I'd roll with something along those lines:
ActiveRecord::Base.establish_connection(
:adapter => 'jdbc',
:driver => 'org.postgresql.Driver',
:url => 'jdbc:postgresql:sample_db;create=true'
:user => 'myuser'
:password => 's3cret!'
)
Alternatively, there's JRuby-PG
Regards,
So the example here worked..
https://github.com/jruby/jruby/wiki/JDBC
def vegetableFinder(vegetable)
# This function takes a hashmap of vegetables and attempts to
# find them from our grocery database. For each item found, we
# call our 'makevegetablesoup' function.
# Load all required gems
require "rubygems"
require "jdbc/mysql"
require "java"
begin
# Prep the connection
Java::com.mysql.jdbc.Driver
userurl = "jdbc:mysql://HOST/DATABASE"
connSelect = java.sql.DriverManager.get_connection(userurl, "USERNAME", "PASSWORD")
stmtSelect = connSelect.create_statement
# Define the query
selectquery = %q{SELECT name, type, size, price
FROM vegetables
WHERE type = "#{vegetable["type"]}"
AND size = "#{vegetable["size"]}}
# Execute the query
rsS = stmtSelect.execute_query(selectquery)
# For each row returned do some stuff
while (rsS.next) do
veg = Hash.new
veg["vegname"] = rsS.getObject("name")
veg["vegtype"] = rsS.getObject("type")
veg["vegprice"] = rsS.getObject("size")
veg["vegsize"] = rsS.getObject("price")
makevegetablesoup(veg)
end
end
# Close off the connection
stmtSelect.close
connSelect.close
return truth
end