How to fetch two associated Database values Using Rails 3 - ruby

Question

Hi I have two tables in DB.The first table is given below.
Table name-
t_hcsy_details
class name in model-
class THcsyDetails < ActiveRecord::Base
end
The values in side table is given below.
HCSY_Details_ID HCSY_ID HCSY_Fund_Type_ID Amount
1 2 1 1125
2 2 2 390
3 2 3 285
4 2 4 100
5 2 5 60
6 2 6 40
My second table is given below.
Table Name:
t_hcsy_fund_type_master
class in model:
class THcsyFundTypeMaster < ActiveRecord::Base
end
Table values are given below.
HCSY_Fund_Type_ID Fund_Type_Code Fund_Type_Name Amount
1 1 woods 1125
2 2 Burning 390
3 3 goods 285
4 4 brahmin 100
5 5 swd 60
6 6 Photo 40
I know only HCSY_ID value(i.e-2) of first table.But i need Fund_Type_Name and Amount from second table.As you can see one HCSY_ID has 6 different records.But i need all Fund_Type_Name and Amount of one HCSY_ID. Please help me to resolve this issue by creating object for both two classes shown above.Please help me.

Answer 1

You haven't specified any relationships setup, so it would be easier to split this in two queries:
# you already have hcsy_id
fund_type_ids = THcsyDetails.where(hcsy_id: hcsy_id).pluck(:hcsy_fund_type_id)
fund_types = THcsyFundTypeMaster.where(id: fund_type_ids)
fund_types.group(:fund_type_name).sum(:amount)
In case you had proper relationships setup, the above would've simplified to:
THcsyDetails.
joins(association_name). # THcsyFundTypeMaster
where(hcsy_id: hcsy_id).
group("#{t = THcsyFundTypeMaster.table_name}.fund_type_name").
sum("#{t}.amount")