Difference of data between gl_balances & gl_je_lines

Hi,

We are getting different data against below queries if running for some accounts & getting same data for other accounts. We assume that the data will be same against both the queries for correct accounts & will be different for problematic accounts.

select SUM(NVL(ENTERED_DR,0))ENTERED_DR, SUM(NVL(ENTERED_CR,0))ENTERED_CR, SUM(NVL(ENTERED_DR,0)-NVL(ENTERED_CR,0))BALANCE

from gl_je_lines

where period_name='NOV-14' CODE_COMBINATION_ID=XXXX;

select sum(period_net_dr), sum(period_net_cr), sum(period_net_dr-period_net_cr)

from gl_balances

where  period_name='NOV-14' and  CODE_COMBINATION_ID=XXXX;