sum total column of a table - ruby-on-rails

Question

I have a this query in rails:
def self.nominas(params)
query = select("payroll_employees.*,payroll_employees.total, concat(e.name, ' ', e.surname, ' ', e.other_surname) as nombre_empleado, ec.code as contrato, CASE WHEN payroll_employees.is_wage_integral = TRUE THEN 'Si' WHEN payroll_employees.is_wage_integral = FALSE THEN 'No' END AS salario_es_integral, pc.integral_wage AS p_c_integral_wage")
query = query.joins("inner join payrolls p on (p.id = payroll_employees.payroll_id) inner join employee_contracts ec on (ec.id = payroll_employees.employee_contract_id) inner join employees e on (e.id = ec.employee_id) inner join payroll_companies pc on (pc.company_id = p.company_id) ")
query = query.where('p.id = :nomina', {nomina: params[:id] })
query = query.group(:id, 'e.name', 'e.surname', 'e.other_surname', 'ec.code', 'pc.integral_wage')
query = query.having("(lower(concat(e.name, ' ', e.surname, ' ', e.other_surname)) LIKE :campo_busqueda or :campo_busqueda = '') OR (lower(ec.code) LIKE :campo_busqueda or :campo_busqueda = '')", {campo_busqueda: "%#{params[:buscador].try(:downcase)}%"})
query = query.order('nombre_empleado')
end
in which I have a column "total", and I need to do the summation of the column "total" of all the records that the query brings me, my problem comes at the time of doing this:
#payroll_employees = PayrollEmployee.nominas(params)####
#sum_total = #payroll_employees.sum(:total)
it brings me something like this:
{[345, "Angel", "BONILLA", "MONTAÑO", "2010", true]=>0.106215575500000000000001e7, [079, "Bill f", "CABRERA", "RICO", "1846", true]=>0.1330346e7, ...
it seems to me that it is because my query has a group. Is it possible to do the summation and get a single number instead of a grouped array of totals?

Answer 1

Try to use sum function on total sum(payroll_employees.total)
def self.nominas(params)
query = select("payroll_employees.*,sum(payroll_employees.total) as total, concat(e.name, ' ', e.surname, ' ', e.other_surname) as nombre_empleado, ec.code as contrato, CASE WHEN payroll_employees.is_wage_integral = TRUE THEN 'Si' WHEN payroll_employees.is_wage_integral = FALSE THEN 'No' END AS salario_es_integral, pc.integral_wage AS p_c_integral_wage")
query = query.joins("inner join payrolls p on (p.id = payroll_employees.payroll_id) inner join employee_contracts ec on (ec.id = payroll_employees.employee_contract_id) inner join employees e on (e.id = ec.employee_id) inner join payroll_companies pc on (pc.company_id = p.company_id) ")
query = query.where('p.id = :nomina', {nomina: params[:id] })
query = query.group(:id, 'e.name', 'e.surname', 'e.other_surname', 'ec.code', 'pc.integral_wage')
query = query.having("(lower(concat(e.name, ' ', e.surname, ' ', e.other_surname)) LIKE :campo_busqueda or :campo_busqueda = '') OR (lower(ec.code) LIKE :campo_busqueda or :campo_busqueda = '')", {campo_busqueda: "%#{params[:buscador].try(:downcase)}%"})
query = query.order('nombre_empleado')
end