<VALUE-OF>if (reportContext.getPersistentGlobalVariable("runningbalance") == null){
	if (row["amount"] == null){
		temp = 0;
	}
	else{
		temp = row["amount"];
		reportContext.setPersistentGlobalVariable("runningbalance", temp.toString());
	}
}
else{
	temp = parseInt(reportContext.getPersistentGlobalVariable("runningbalance")) + row["amount"]
	reportContext.setPersistentGlobalVariable("runningbalance", temp.toString());
}
temp;</VALUE-OF>

select c.accno, date_trunc('quarter', ac.transdate) as quarter,
sum(ac.amount) as qtot, 
sum(sum(ac.amount)) over (partition by accno order by date_trunc('quarter', ac.transdate)) as balance
from chart c 
left join acc_trans ac on (c.id = ac.chart_id)  
group by c.accno, date_trunc('quarter', ac.transdate);

with 

-- GENERATE SOME RANDOM DATA --
chart as (
	select 1 id, 12345 accno union all
	select 2 id, 23456 accno union all
	select 3 id, 34567 accno)
,

acc_trans as (
	select '2010-01-01'::date transdate, 100.0 amount, 1 chart_id union all
	select '2010-04-01'::date transdate, 100.0 amount, 1 chart_id union all
	select '2010-10-01'::date transdate, 100.0 amount, 1 chart_id union all
	select '2010-10-01'::date transdate, 100.0 amount, 2 chart_id union all
	select '2010-01-01'::date transdate, 100.0 amount, 2 chart_id union all
	select '2010-10-01'::date transdate, 100.0 amount, 3 chart_id)

-- CALCULATE OUTPUT

-- 1) aggregate transactions
,
trans_aggregation as (
select 
	c.accno, 
	c.id,
	date_trunc('quarter', ac.transdate) as granularity,
	sum(ac.amount) as qtot
from 
	chart c 
	left join acc_trans ac on (c.id = ac.chart_id)
group by 
	c.accno,
	date_trunc('quarter', ac.transdate),
	c.id

)

-- 2) calculate running sum
select
	d.granularity,
	d.id,
	coalesce(sum(qtot) over (partition by d.id order by granularity rows between unbounded preceding and current row),0.0) as qtot
from
	(select 
		* 
	from 
		(SELECT generate_series('2010-01-01'::date::timestamp with time zone, Now()::date::timestamp with time zone, '3 months '::interval)::date AS granularity) a ,  -- generate quarters
		(select id from chart) b -- and create product with account id
	) d
	left join trans_aggregation using (granularity, id)